1. Field of the Invention
The present invention relates to a support system for inputting appropriate genotype data into an analysis system in gene analysis to identify genes associated with phenotypes of diseases, physical appearance features or the likes in individuals.
2. Background Art
Genome mapping has been advanced for the human, animals and plants and analytical studies on gene functions are actively under progress. Of those studies, attract a particular attention studies through analysis of linkage disequilibrium which are to search the genome for genes associated with phenotypes (traits) of diseases, physical appearance features or the likes in individuals. As shown in
Such a polymorphic occurrence of a single nucleotide in the genome among individuals is called SNP (single nucleotide polymorphism). A single locus is typically occupied by either of two different nucleotides (for example, A and T), but may be occupied by any one of three or more different nucleotides (for example, A, T and G) in very rare cases. In the case shown in
A case where the same locus is occupied by A in an individual but by no nucleotide in another individual, or a similar case may also happen. In this case, if the first individual views the genome of the latter individual, it is observed to have deletion of a nucleotide A, but if the latter individual views the genome of the first individual, conversely, it is observed to have insertion of the nucleotide A. Such a polymorphic presence/absence of a single nucleotide in the same locus among individuals is called in/del (abbreviation of insertion/deletion) of the single nucleotide.
On the other hand, individuals of many biological species have a pair of genomes (homologous chromosomes) derived from both a female gamete and a male gamete. Genes present at sites corresponding to one another in the pair of genomes are called alleles to one another, and a pair of these alleles is called a genotype. The two alleles may be the same or different since there are different nucleotide sequence portions among individuals in genome. When genes at a particular genomic site are paid attention to, the presence of the same two alleles is called homozygotes, while the presence of different two alleles is called heterozygotes.
When chromosomes are transferred from a parent to a child, the single genome undergoes crossing-over by meiosis and thus gene recombination in the transfer. It is generally believed that two distant genes in the genome are likely to be recombined, but two near genes in the genome are difficult to be recombined. When genes located at two different loci in the genome tend to be transferred from a parent to a child as they are linked, the expression that the two loci have a linkage is used.
Genetic search of hereditary diseases associated with a small number of genes has been conducted up to now by linkage analysis using a program such as “LINKAGE” where data of a large family including at least one patient are input.
It was developed by Rockefeller University in USA. Genotype data of a large family including at least one patient are used for linkage analysis.
On another front, in the search of genes which affect multifactorial diseases attracting current attention (diseases such as lifestyle-related diseases which afflict numerous patients and are probably associated with many genes as well as environmental factors), analysis of linkage disequilibrium is actively conducted for which a general population without blood relationship is used, as described below.
In a single genome derived from either a female gamete or a male gamete, a set of alleles present at multiple linked loci is called a haplotype. Individuals having two homologous genomes in a pair have always two haplotypes in a pair.
A phenomenon may be occasionally observed where the frequency of a certain haplotype for multiple linked loci is significantly different from a frequency which is given by product of frequencies for alleles at the respective loci (the alleles are distributed interdependently among the multiple linked loci). In this case, the expression that those loci are at linkage disequilibrium is used.
The above analysis of linkage disequilibrium can be used to search the genomes of individuals for genes associated with phenotypes (traits) of diseases, physical appearance features or the likes. Two approaches to the analysis will be described below. The first approach will be now described. It is assumed that most of genes responsible to common diseases in a population are formed by mutation of common ancestor genes (common disease common variant assumption). According to the assumption, an SNP allele close to the locus where such mutation occurred would be inherited in a combination with the pathogenic gene. In other words, linkage disequilibrium would be observed between the locus for the pathogenic gene and SNP loci close thereto. Therefore, such a region in the genome is called a linkage disequilibrium block or a haplotype bloc. A haplotype block common to individuals suffering from a certain disease can be searched to identify a gene causing the disease. The second approach will be now described. If the SNP allele close to the mutated gene is inherited to the patient population together with the pathogenic gene, as described above according to the common disease common variant assumption, the frequency of the allele would be different between the patient population and the healthy population. This deduction draws the assumption that conversely, an SNP allele having a different frequency between the patient population and the healthy population would be accompanied by a pathogenic gene close thereto. An approach of combining multiple SNPs to form a haplotype is similarly used to compare its frequency between the patient population and the healthy population.
When genes associated with phenotypes are searched for using linkage disequilibrium analysis, tens to hundreds of individual samples, sometimes at least a thousand of those, are typically used to examine genotypes at several to hundreds of loci, sometimes about ten thousand loci. In addition, many programs for linkage disequilibrium analysis using genotypes as input data have been developed and are now available as described below.
It was developed by University of Geneva in Switzerland. Genotypic data of unrelated individuals are used to test the Hardy-Weinberg equilibrium and calculate for linkage disequilibrium.
Stefan Schneider, David Roessli, and Laurent Excoffier (2000) Arlequin ver. 2000: A software for population genetics data analysis. Genetics and Biometry Laboratory, University of Geneva, Switzerland.
It was developed by Whitehead Institute in USA. Genotypic data of unrelated individuals are used to verify the number of missing samples for each locus, verify the Hardy-Weinberg equilibrium (described later), verify distances among loci, verify the frequencies of minor alleles and calculate for haplotype blocs (see J. C. Barrett, B. Fry, J. Maller and M. J. Daly, “Haploview: analysis and visualization of LD and haplotype maps”, Bioinformatics vol. 21, no. 2 (2005), pages 263-265).
It was developed by Silicon Genetics Inc. in USA (as of filing the present patent application, the same software known as “GeneSpring GT” is available from Agilent Technologies Inc. in USA). Genotypic data of family or unrelated individuals are used to carry out data analyses such as calculation for haplotype blocs.
IUB code, which is described in
In addition, algorithms taking account of distances between loci (by how many nucleotides are the two loci separated?) for calculations have been proposed to determine haplotype blocs. Therefore, location of each locus is necessary to be specified in its input data.
When a pathogenic gene is searched for with the help of a program, it is problematic that false descriptions are present in the input data. The program assumes that the input data given is perfectly correct. However, genotype data obtained experimentally are often processed into electronic data or changed in format in manually, and hence it is almost impossible to completely prevent false descriptions in the input data. In addition to errors made in manual input of the data, errors may be brought in from wrong experimental results. Taking them together, numerous errors may happen.
For conventional linkage analyses, the approach of making sure if genotype data are consistent or not by use of parenthood is presented such as Varia or Checkfam.
It was developed by Tokyo Women's Medical University. Genotypic data with information of families are used to search them for contradiction as to inheritance of alleles.
As for input data for linkage disequilibrium analysis, however, no correction measures have ever been taken though various errors may occur as described below.
Error 1: No Data of Physical Positions of Loci are Provided in the Input Data for a Program Requiring them
In this case, input files are not so adequate as to execute the analysis program.
Error 2: Loci are not Arranged in Order of their Physical Positions (in a Chromosome) in the Input Data for a Program where the Loci are Assumed Arranged Correctly
In this case, the program may abnormally terminate on the way, or analysis results may be different from those intended even if the program can be executed. When the program has been apparently executed to the end, there is a risk that the researcher may not recognize that analysis results are different from those intended.
Error 3: Some Loci are Present in the same Physical Position in the Input Data for a Program where Physical Positions of Loci are not Assumed Overlapped
There is a risk that physical positions of loci may become inconsistent and overlapped depending on how they are re-counted when the genomic sequence data of the chromosome is updated, or how they are counted for in/del polymorphism.
Some SNPs have multiple locus names due to the process of their discovery. In addition, in the description of locus names, “(ABI)” may be appended to the locus names of SNPs developed by Applied Biosystems Inc., and “(JSNP)” may be appended to the locus names of SNPs developed by the JSNP project. In this case, there is a risk that the additional character strings may drop off or turn into double-byte characters while the input data are produced manually. When inconsistent locus names are produced by these causes, a particular locus is processed by a program as if no genotype data therefor were specified/the physical position thereof were not specified. Such a situation is time-consuming to find out a cause for the problem and solve it.
Error 5: Unexpected Character Strings are used to Represent Genotypes
In the IUB codes shown in
Error 6: Individuals Belonging to an Unexpected Population are used/only one of the Populations is Provided in the Input Data for a Program where a Patient Population and a Healthy Population are Intended for Analysis
In the format shown in
Error 7: A Locus Comprising Three or more Alleles is Present
Four causes can be presumed as follows.
The first cause is that three or more alleles have been actually present at the locus, and thus it is not a false description. However, the feature of an experimental technique taken must be considered because the base sequence reading experiment or the use of a DNA microarray allows three or more alleles to be differentiated, but the TaqMan assay or the like may allow only two alleles to be differentiated. Some programs directed to SNP are based on the assumption that each locus has two alleles. In such programs, a relevant locus must be removed from the analysis, or the least frequent allele must be combined with the most frequent allele.
The second cause is that a heterozygous genotype has been described by mistake. In 3600 in
The third cause is that missing data has been described as a blank character (a one-byte space, tab or the like) rather than “0”. In
The fourth cause is that a heterozygous genotype has been described by mistake. In
In the cases of the third and fourth causes, it is not only difficult to associate the false description with the abnormal termination of the program, but also almost impossible to find out the false description among a large amount of the data including samples from 1,000 or more individuals and hundreds of loci. Such a situation is time-consuming to find out a cause for the problem and solve it.
Error 8: Loci Lack of Polymorphism are Contained in the Input Data for a Program where every Locus is Assumed to Display Polymorphism
When researchers use loci registered in a public data base such as JSNP, the loci are described as polymorphic in the data base, but may not be polymorphic (monomorphic) in the samples of the researchers. Some algorithms of linkage disequilibrium analysis are defined under the assumption that every locus used in the analysis displays polymorphism. For instance, a linkage disequilibrium measure, D′ is determined by calculation using the frequencies of alleles in a divisor. Accordingly, the measure is not defined for a locus having an allele with zero frequency. If non-polymorphic loci are contained in the input data for such a program, the program could abnormally terminate on the way, or analysis results could be different from those intended even if the program can be executed.
Error 9: In/del Polymorphism is Contained in the Input Data for a Program where nothing other than A, T, G or C is Assumed to Appear in Alleles
In this situation, the program could abnormally terminate on the way, or analysis results could be different from those intended even if the program can be executed.
Error 10: An Extraordinarily Great Number of Individuals have the same Heterozygous Locus
To study genotypes experimentally, a short nucleotide sequence called a probe is provided for each locus in many cases. In SNP samples provided by JSNP or Applied Biosystems Inc., it may be expected that the probe is confirmed to react with only one location on the genome, but in SNP samples registered in a public data base such as dbSNP, which can be accessed by the general public, or in SNP samples provided by researchers on their own, the probe may react with two locations, though it is rare, as shown in 3700 of
Error 11: An Extraordinarily Great Number of Individuals have the same Homozygous Locus
There are two conceivable causes. The first cause is that a sample population comprises many samples containing such homozygote samples. For diseases which may be caused by homozygous mutation at a higher risk than by heterozygous mutation, a patient population may be homozygote more frequently. The second cause is that the sample population is composed of two populations. For instance, there is now assumed to be a locus 3 where every individual of human race 1 has C and every individual of human race 2 has G. If the sample population comprises the two human races, the resultant data seem as if the locus displayed polymorphism, as shown in
Error 12: Some Individuals have an Extraordinarily Great Number of Heterozygous Loci
There may happen a case where one sample is accidentally contaminated by a portion of another sample during the experiment. In the state shown in 3900 of
Error 13: Some Individuals have an Extraordinarily Great Number of Homozygous Loci
In a case shown in
Error 14: Some Individuals have many Missing Data
As shown in
Error 15: Some Loci have many Missing Data
As shown in
Error 16: The Sample Population Deviates from the Hardy-Weinberg Equilibrium
When a population has a good number of individuals and has the conditions that: no individuals immigrate into a different population; random mating in population is made; and neither mutations nor natural selections occur, the population is said to be in Hardy-Weinberg equilibrium. If the sample population used in the analysis deviates from Hardy-Weinberg equilibrium, it will be doubtful if the samples have been taken randomly, and a suitable analysis could not be made.
Error 17: Some of the Loci used in the Analysis are Extremely Distant from the other Loci
When the distance between the loci is very long, it is highly unlikely to think that the loci are in linkage disequilibrium (the loci are inherited as a bunch from the ancestor). Therefore, these loci should not be analyzed at once for linkage disequilibrium.
Error 18: Some Loci have Extremely Rare Alleles
In a search for pathogenic genes by statistical gene analysis, it is usually considered desirable to analyze only loci having a minor allele with a frequency of at least 5%, preferably of at least 10 to 30%. This limitation is set to prevent the power of statistic test from lowering by use of loci having alleles with an extremely low frequency. Accordingly, it is preferable to make both an analysis including the data for the locus and an analysis excluding them.
It is the object of the present invention to provide a data input support system which can preliminarily detect and remove such causes of errors as described above in making entries of genotype data for a program to execute linkage disequilibrium analysis or the like.
As a result of every effort to solve the problem described above, the present inventors have now proposed a data input support system wherein, paying attention to limiting conditions characteristic of genotype input data and the statistical properties of the entire data set, the types of possible errors are preliminarily assumed, the input data are preprocessed to detect these errors, and the detected errors are associated with false descriptions causing them in order to report the results to the user. By means of such a data input support system, linkage disequilibrium analysis using appropriate data can be conducted efficiently, and the output of analysis results contrary to the user's intention can be avoided. More specifically, the following functions 1 to 15 will be used as means to correct the above errors 1 to 15, respectively.
Function 1: the system retains information as to if each analysis program needs the physical positions of loci as input data, and if an analysis program specified by a user needs the specified physical positions of loci, but they have not yet been specified in the input data, the system reports it.
Function 2-1: the system retains information as to if each analysis program assumes the arrangement of loci in order of their physical positions, and if an analysis program specified by a user assumes the arrangement of loci in order of their physical positions, but such arrangement is not provided in the input data, the system reports it.
Function 2-2: if Function 2-1 applies, the system produces a modified version of the input data having the loci rearranged.
Function 3: the system checks if the physical positions of loci overlap, and if they overlap, the system reports it.
Function 4-1: the system checks if loci having genotypes unspecified in every individual and loci having physical positions unspecified are present. If such a set of loci is present, the system checks if the loci have similar names, and if the loci have similar names, the system reports possible false descriptions of the names of the loci.
Function 4-2: if Function 4-1 applies, the system produces a modified version of the input data having the names of the loci made uniform into one of the names.
Function 5-1: the system checks if a symbol such as “*” (asterisk) is specified as genotype data, and if genotypes have such a symbol, the system reports possible false descriptions of the missing data.
Function 5-2: if Function 5-1 applies, the system produces a modified version of the input data having the descriptions of the genotypes replaced by “0” for missing data.
Function 5-3: the system checks if continuous form of two alleles such as AT are specified as genotype data, and if genotypes have such character strings, the system reports possible false descriptions of the heterozygous genotypes.
Function 5-4: if Function 5-3 applies, the system produces a modified version of the input data having the replaced descriptions of the heterozygous genotypes.
Function 5-5: the system checks if unexpected character strings such as “N” are specified as genotype data, and if genotypes have such character strings, the system reports it.
Function 6-1: the system retains information as to if each analysis program assumes the use of patients and healthy persons as input data, and if an analysis program specified by a user assumes the use of patients and healthy persons as input data, but the names of their populations are unspecified, the system reports it.
Function 6-2: the system checks if “Case” or “Control” is specified as population name, or an erroneously spelled name for “Patient” or “Normal” is specified where capital and/or small letters are wrongly used, and reports such a possible false description of “Patient” or “Normal”.
Function 6-3: if Function 6-2 applies, the system produces a modified version of the input data having the descriptions of the population names replaced by “Patient” or “Normal”.
Function 6-4: the system retains information as to if each analysis program assumes the use of patients and healthy persons as input data, and if an analysis program specified by a user assumes the use of patients and healthy persons, but an unexpected character string such as “Japanese” is specified as population name, the system reports it.
Function 7-1: the system retains information as to if each analysis program assumes the presence of two alleles at each locus and information as to what experimental technique is taken for each locus, and if an analysis program specified by a user assumes the presence of two alleles, or such an experimental technique is taken as can discriminate only two alleles, but loci with three or more alleles are actually present, the system reports it.
Function 7-2: if Function 7-1 applies, the system produces a modified version of the input data where those loci are excluded from the input data to be analyzed.
Function 7-3: if Function 7-1 applies, the system produces a modified version of the input data where the most frequent allele is combined with a third or higher-numbered most frequent allele in those loci.
Function 7-4: the system checks if there are loci having three or more alleles. If such loci are present, the system checks if both conditions described below are satisfied. If both of the conditions are satisfied, the system reports possible false descriptions of genotypes where the most frequent two of the alleles are heterozygous. 1) The most frequent two of the alleles are developed only as homozygotes, and there are no individuals having heterozygotes between the most frequent two of the alleles. 2) A third or higher-numbered most frequent allele is developed only as heterozygotes, and there are no individuals having homozygotes between the third and higher-numbered most frequent alleles.
Function 7-5: if Function 7-4 applies, the system produces a modified version of the input data having the heterozygous genotypes rewritten.
Function 7-6: the system checks if there is a locus having three or more alleles. If such a locus is present, the system checks if all of the four conditions described below are satisfied. If all of the four conditions are satisfied, the system reports possible descriptions of missing data as blank characters (a one-byte space, tab or the like). 1) A number of loci having three or more alleles appear which are more highly numbered than the above locus. 2) It is the same individual that has a third or higher-numbered most frequent allele at each locus having three or more alleles. 3) In the individual having a third or higher-numbered most frequent allele in common, the genotype at the last locus is not specified. 4) A third or higher-numbered most frequent allele at each locus having three or more alleles appears as a first or second most frequent allele at the next right locus.
Function 7-7: if Function 7-6 applies, the system produces a modified version of the input data having the descriptions of missing data replaced by “0”.
Function 7-8: the system checks if there is a locus having three or more alleles. If such a locus is present, the system checks if all of the four conditions described below are satisfied. If all of the four conditions are satisfied, the system reports possible description of a heterozygous genotype by two alleles separated by a one-byte space. 1) A number of loci having three or more alleles appear which are more highly numbered than the above locus. 2) It is the same individual that has a third or higher-numbered most frequent allele at each locus having three or more alleles. 3) In the individual having a third or higher-numbered most frequent allele in common, the last locus with no specified locus name has a specified genotype. 4) A third or higher-numbered most frequent allele at each locus having three or more alleles appears as a first or second most frequent allele at the next left locus.
Function 7-9: if Function 7-8 applies, the system produces a modified version of the input data having the heterozygous genotype rewritten.
Function 7-10: the system checks if blank characters (a one-byte space, tab or the like) are irregularly used. If any of the following three conditions is satisfied, the system reports possible interpretation of the input data contrary to the intention of a user. 1) Two or more kinds of blank characters are used as break character for the input data. 2) Two or more blank characters appear in succession. 3) Such characters (a double-byte space or the like) as may be interpreted as either blank character or data are used.
In the IUB coding system, an individual identifier and locus data, or locus data to each other are assumed to be separated by a blank character (a one-byte space, tab or the like), typically a tab. However, since blank characters are not displayed on the screen by a usual text editor, two or more kinds of blank characters may be present one after another, or a double-byte space may be accidentally input in stead of a one-byte space, or an unnecessary blank character may be input at the end of a line. Furthermore, since a usual spreadsheet software interprets data by tab delimitation and displays each column of data in a vertical arrangement, a user may possibly not recognize that genotype data have been missed out, or described as a one-byte or double-byte space, or described as two alleles separated by a one-byte space. Error 7 described above can be securely prevented by utilizing Function 7-10 to report the irregular uses of blank characters.
Function 8-1: the system retains information as to if each analysis program assumes every locus to be polymorphic, and if an analysis program specified by a user assumes polymorphism in such a way, but some loci are monomorphic, the system reports it.
Function 8-2: if Function 8-1 applies, the system produces a modified version of the input data where the loci are excluded from the input data to be analyzed.
Function 9-1: the system retains information as to if each analysis program assumes nothing but A, T, G and C as allele, and if an analysis program specified by a user assumes nothing but A, T, G and C as allele, but some loci are in/del polymorphic, the system reports it.
Function 9-2: if Function 9-1 applies, the system produces a modified version of the input data where the in/del polymorphic loci are excluded.
Function 10-1: the system checks if there are loci heterozygous in extremely many individuals, and if such loci are present, the system reports possible reaction of probes for the loci at two or more locations on the genome.
Function 10-2: if Function 10-1 applies, the system produces a modified version of the input data where the loci are excluded from the input data to be analyzed.
Function 11: the system checks if there are loci homozygous in extremely many individuals, and if such loci are present, the system reports a possible presence of two or more populations in the sample population.
Function 12-1: the system checks if there are individuals having extremely many heterozygous loci, and if such individuals are present, the system reports a possible contamination.
Function 12-2: if Function 12-1 applies, the system produces a modified version of the input data where the individuals are excluded from the input data to be analyzed.
Function 13-1: the system checks if there are individuals having extremely many homozygous loci, and if such individuals are present, the system reports a possible peculiarity of the individuals.
Function 13-2: if Function 13-1 applies, the system produces a modified version of the input data where the individuals are excluded from the input data to be analyzed.
Function 14-1: the system checks if there are individuals having many missing data, and if such individuals are present, the system reports it.
Function 14-2: if Function 14-1 applies, the system produces a modified version of the input data where the individuals are excluded from the input data to be analyzed.
Function 15: the system lists and displays both the items reported using Functions 1 to 14-2 described above and the items for which modified versions of the input data have been produced.
Errors 1 to 14 can be prevented by use of Functions 1 to 14-2, respectively. In addition, Errors 15, 16, 17 and 18 can be dealt with by conventional techniques such as Haploview and Varia described above.
The present invention provides, as a system having the above Functions 1 to 15, a data input support system to inspect genotype data which are input into a program for linkage disequilibrium analysis, wherein the system comprises a storage section for retaining error types for genotype data corresponding to the program for linkage disequilibrium analysis, an error detection section for checking the input genotype data for the error types and detecting errors, and an error report/display section for displaying the report of the detected errors.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data has no data on the physical positions of loci, opposed to a program for linkage disequilibrium analysis requiring genotype data on the physical positions of the loci. This provides the above Function 1.
In the inventive data input support system, the error types are characterized by comprising the error that in the input genotype data, the loci are not arranged in order of their physical positions, opposed to a program for linkage disequilibrium analysis corresponding only to genotype data where the loci are arranged in order of their physical positions. This provides the above Function 2 (branch number is omitted, and it will be omitted hereafter).
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data has the physical positions of loci overlapped. This provides the above Function 3.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains loci having genotypes unspecified and loci having physical positions unspecified. This provides the above Function 4.
In the inventive data input support system, the error types are characterized by comprising the error that in the input genotype data, some symbols denoting a homozygote, a heterozygote or missing data are different from those defined by the program for linkage disequilibrium analysis. This provides the above Function 5.
In the inventive data input support system, the error types are characterized by comprising the error that in the input genotype data, neither a patient population nor a healthy population is specified according to the definitions made by a program for linkage disequilibrium analysis, opposed to the program for linkage disequilibrium analysis requiring the genotype data of both patients and healthy persons. This provides the above Function 6.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains loci having three or more alleles, opposed to a program for linkage disequilibrium analysis defining that at most two alleles are present in a locus. This provides the above Function 7.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains any of the following descriptions:
This provides the above Function 7.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains monomorphic loci, opposed to a program for linkage disequilibrium analysis defining that every locus is polymorphic. This provides the above Function 8.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains in/del polymorphic loci, opposed to a program for linkage disequilibrium analysis defining that nothing but A, T, G or C appears as allele. This provides the above Function 9.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains a higher level of individuals where the locus is heterozygous than a predetermined level, or a higher level of individuals where the locus is homozygous than a predetermined level. Herein, the predetermined level may be selected from a rate of number of individuals, a P value in a statistical test, or the like. This provides the above Functions 10 and 11.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains individuals having a higher level of heterozygous loci than a predetermined level, or individuals having a higher level of homozygous loci than a predetermined level. Herein, the predetermined level may be selected from a rate of number of individuals, a P value in a statistical test, or the like. This provides the above Functions 12 and 13.
In the inventive data input support system, the error types are characterized by comprising the error that the input genotype data contains individuals having a higher level of missing data than a predetermined level. Herein, the predetermined level used may be a rate of number of individuals or the like. This provides the above Function 14.
In the inventive data input support system, the above Function 7 has further characteristics as described below.
If genotype data contain loci having three or more alleles, and both conditions described below are satisfied, the error report/display section displays a report on possible false descriptions in the input genotype data of genotypes where the most frequent two of the three or more alleles are heterozygous.
If genotype data contain a locus having three or more alleles, and the four conditions described below are satisfied, the error report/display section displays a report on possible false descriptions in the input genotype data of missing data.
If genotype data contain a locus having three or more alleles, and the four conditions described below are satisfied, the error report/display section displays a report on possible false description in the input genotype data of a heterozygous genotype.
In addition, the inventive data input support system is characterized by also comprising error correction means to accept an input for correcting the reported error in the input genotype data and correct the input genotype data based on the input.
In the inventive data input support system, the error correction means is characterized by accepting a correction input by which for the locus having three or more alleles, a third or higher-numbered most frequent allele of the three or more alleles is rewritten into a first or higher-numbered most frequent allele, and thereby correcting the genotype data in such a manner.
The inventive data input support system is characterized by further comprising means to display as a list the content of errors reported by the error report/display section as well as the content of corrections for the genotype data by the error correction means.
According to the present invention, as described above, various errors can be detected which are contained in data to be input for a program for linkage disequilibrium analysis or the like, and the errors can be associated with false descriptions resulting in the errors to display the results. In this way, the linkage disequilibrium analysis can be conducted efficiently using appropriate data, and the output of analysis results contrary to the intention of a user can be avoided.
The best embodiment to carry out the inventive data input support system for gene analysis will be described below in detail referring to the appended drawings.
The program memory 105 contains: a specified physical position report processing section 107 for execution of the above Function 1; a physical position order report processing section 108 for execution of Functions 2-1 and 2-2; a physical positions overlap report processing section 109 for execution of Function 3; a similar locus name report processing section 110 for execution of Functions 4-1 and 4-2; a genotype report processing section 111 for execution of Functions 5-1, 5-2, 5-3, 5-4 and 5-5; a population name report processing section 112 for execution of Functions 6-1, 6-2, 6-3 and 6-4; an allele number report processing section 113 for execution of Functions 7-1, 7-2, 7-3, 7-4, 7-5, 7-6, 7-7, 7-8, 7-9 and 7-10; a monomorphism report processing section 114 for execution of Functions 8-1 and 8-2; an in/del report processing section 115 for execution of Functions 9-1 and 9-2; a dual site reaction report processing section 116 for execution of Functions 10-1 and 10-2; a plural populations report processing section 117 for execution of Function 11; a contamination report processing section 118 for execution of Functions 12-1 and 12-2; a special individual report processing section 119 for execution of Functions 13-1 and 13-2; a missing individual report processing section 120 for execution of Functions 14-1 and 14-2; and a reported/corrected items display processing section 121 for execution of Function 15. Additionally, the genotype report processing section 111 comprises a symbol genotype report processing section 122 for execution of the above Functions 5-1 and 5-2, a character string genotype report processing section 123 for execution of Functions 5-3 and 5-4, and an unexpected genotype report processing section 124 for execution of Function 5-5; the population name report processing section 112 comprises a specified population name report processing section 125 for execution of the above Function 6-1, a falsely described population name report processing section 126 for execution of Functions 6-2 and 6-3, and an unexpected population name report processing section 127 for execution of Function 6-4; and the allele number report processing section 113 comprises a multiple alleles report processing section 128 for execution of the above Functions 7-1, 7-2 and 7-3, a falsely described heterozygosis report processing section 129 for execution of Functions 7-4 and 7-5, a missing blank report processing section 130 for execution of Functions 7-6 and 7-7, a heterozygosis blank report processing section 131 for execution of Functions 7-8 and 7-9, and an irregular blank character report processing section 132 for execution of Function 7-10.
The data memory 106 comprises program data 133 containing the features of programs used in statistical gene analysis and input data 134 used as input data for the programs.
The data structure LocusData comprises each locus name 303, its physical position 304 and an experimental protocol 305 used to determine the genotype at each locus for the number of loci, integer i.
The data structure IndividualData comprises: an individual identifier 306 for each individual; a population name 307 indicating the name of the population to which the individual belongs; a genotype data 308 indicating respective genotypes which the individual has at respective loci; and an original character string 309 in the input data, for the number of individual samples, integer j. The genotype data 308 represents an array for storing genotype data interpreted by separating the input data 309 into compartments with blank characters, and has the number of elements equal to the number of elements, integer i, in the locus data 301.
Next, processings executed in the genotype data input support system of the present embodiment will be now described which system is configured as described above.
Next, the processing for checking and reporting if there are errors in the input data, and accepting user input, which is executed in step 402 in
Next, it is checked if the input loci are arranged in the order of their physical positions, and the results are reported and corrected (step 501), using the physical position order report processing section 108. If the physical position order flag 202 in the program data 133 is TRUE, the physical position 304 of the locus data 301 in the input data 134 is investigated one after another. If some specified physical positions present a reversed magnitude correlation, an error is judged to be present and it is displayed on the screen as shown in
Next, it is checked and reported if the physical positions of the loci are overlapped, using the physical positions overlap reporting/processing section 109 (step 502). The physical position 304 of the locus data 301 in the input data 134 is investigated one after another, and if some of the physical positions have the same number, an error is judged to be present and it is displayed on the screen as shown in
Next, it is checked if a locus name is falsely described, and the results are reported and corrected (step 503), using the similar locus name report processing section 110. As described in the above Function 4-1, it is checked if there is a locus in which the genotype data 308 in the input data 134 are unspecified in every individual and there is a locus in which the physical position 304 is unspecified. If such a set of loci is present, and the loci have similar names, an error is judged to be present and it is displayed on the screen as shown in
Next, it is checked if an unexpected genotype is present, and the results are reported and corrected (step 504), using the genotype reporting/processing section 111. This processing will be described in detail referring to
Next, it is checked if a population name is erroneous, and the results are reported and corrected (step 505), using the population name reporting/processing section 112. This processing will be described in detail referring to
Next, it is checked if a locus having three or more alleles is present, and the results are reported and corrected (step 506), using the allele number reporting/processing section 113. This processing will be described in detail referring to
Next, it is checked if a monomorphic locus is present, and the results are reported and corrected (step 507), using the monomorphism reporting/processing section 114. If the monomorphism exclusion flag 205 in the program data 133 is TRUE, and the genotype data 308 in the input data 134 is not polymorphic, an error is judged to be present and it is displayed on the screen as shown in
Next, it is checked if a locus containing in/del polymorphism is present, and the results are reported and corrected (step 508), using the in/del reporting/processing section 115. If the in/del exclusion flag 206 in the program data 133 is TRUE, and the genotype data 308 in the input data 134 is in/del polymorphic, an error is judged to be present and it is displayed on the screen as shown in
Next, it is checked if there is a locus heterozygous in extremely many individuals, and the results are reported and corrected (step 509), using the dual site reaction reporting/processing section 116. For each locus, the number rate of individuals having the heterozygous locus in the total individuals (heterozygosity), the occurrence probability of the locus with an observed heterozygosity (P value in the Hardy-Weinberg equilibrium test) or the like is used to evaluate the abundance of individuals heterozygous at the locus. If there is a locus heterozygous in extremely many individuals, it is displayed on the screen as shown in
Next, it is checked and reported if there is a locus homozygous in extremely many individuals (step 510), using the plural populations report processing section 117. For each locus, the number rate (homozygosity) of individuals having the homozygous locus in the total individuals, the occurrence probability (P value in the Hardy-Weinberg equilibrium test) of the locus with an observed homozygosity or the like is used to evaluate the abundance of individuals homozygous at the locus. If there is a locus homozygous in extremely many individuals, it is displayed on the screen as shown in
Next, it is checked if there is an individual having extremely many heterozygous loci, and the results are reported and corrected (step 511), using the contamination report processing section 118. For each individual, the number rate of the heterozygous loci in the total loci, the occurrence probability (P value) of the individual with an observed number rate or the like is used to evaluate the abundance of heterozygous loci. If there is an individual having extremely many heterozygous loci, it is displayed on the screen as shown in
Next, it is checked if there is an individual having extremely many homozygous loci, and the results are reported and corrected (step 512), using the special individual reporting/processing section 119. For each individual, the number rate of the homozygous loci in the total loci, the occurrence probability (P value) of the individual with an observed number rate or the like is used to evaluate the abundance of homozygous loci. If there is an individual having extremely many homozygous loci, it is displayed on the screen as shown in
Next, it is checked if there is an individual having many missing data, and the results are reported and corrected (step 513), using the missing individual reporting/processing section 120. The number rate of the missing data in the total loci is used to evaluate the abundance of missing data. If there are far more missing data than a predetermined reference level, it is displayed on the screen as shown in
Next, the reported items and items for each of which a modified version of the input data was produced in steps 500 to 513 are listed up and displayed on the screen as shown in
Next, the processing for checking if there is an unexpected genotype, and reporting and correcting the results, which is executed in step 504 in
Next, it is checked if a character string of two alleles is specified as genotype data, and the results are reported and corrected (step 601), using the character string genotype report processing section 123. If there is such a genotype, it is displayed on the screen as shown in
Next, it is checked and reported if an unexpected character string is specified as genotype data (step 602), using the unexpected genotype report processing section 124. If there is such a genotype, it is displayed on the screen as shown in
Next, the processing for checking if a population name is erroneous, and reporting and correcting the results, which is executed in step 505 in
Next, it is checked if “Case” or “Control” is specified as population name, or an erroneously spelled name for “Patient” or “Normal” is specified where capital and/or small letters are wrongly used, and the results are reported and corrected (step 701), using the falsely described population name reporting/processing section 126. If there is an individual with such a population name specified, it is displayed on the screen as shown in
Next, it is checked and reported if an unexpected character string is specified as population name (step 702), using the unexpected population name report processing section 127. If there is an individual with such a population name specified, it is displayed on the screen as shown in
Next, the processing for checking if there is a locus having three or more alleles, and reporting and correcting the results, which is executed in step 506 in
It is checked if a heterozygous genotype is accidentally described as two alleles separated by a one-byte space, and the results are reported and corrected (step 801) as described in Function 7-8, using the heterozygosis blank report processing section 131. If such a description has occurred, it is displayed on the screen as shown in
It is checked if a heterozygous genotype is falsely described, and the results are reported and corrected (step 802) as described in Function 7-4, using the falsely described heterozygosis reporting/processing section 129. If there is a locus with a heterozygous genotype falsely described, it is displayed on the screen as shown in
It is checked if a locus having three or more alleles is present, and the results are reported and corrected (step 803) as described in Function 7-1, using the multiple alleles reporting/processing section 128. If the multiple alleles exclusion flag 204 in the program data 133 is TRUE, or the experimental protocol 305 in the input data 134 can discriminate only two alleles, the genotype data 308 in the input data 134 are searched for a locus having three or more alleles. If such a locus is present, it is displayed on the screen as shown in
Next, it is checked and reported if a blank character is used irregularly (step 804) as described in Function 7-10, using the irregular blank character reporting/processing section 132. In investigating each individual for input data 309, if two or more kinds of blank characters are used as break character for the input data, or two or more blank characters appear in succession, or such characters (a double-byte space or the like) as may be interpreted as either blank character or data are used, blank characters are judged to be used irregularly. If it happens, it is displayed on the screen as shown in
Herein, only the IUB coding system has been described, but the format of data opened by the HapMAP project can also employ the sections used here consisting of: a physical position order report processing section 108; a physical positions overlap report processing section 109; a symbol genotype report processing section 122, a character string genotype report processing section 123, and an unexpected genotype report processing section 124 within a genotype report processing section 111; a multiple alleles report processing section 128 and an irregular blank character report processing section 132 within an allele number report processing section 113; a monomorphism report processing section 114; an in/del report processing section 115; a dual site reaction report processing section 116; a plural populations report processing section 117; a contamination report processing section 118; a special individual report processing section 119; a missing individual report processing section 120; and a reported/corrected items display processing section 121.
Also, the input data format of ARLEQUIN can employ the sections used here consisting of: a symbol genotype report processing section 122 and an unexpected genotype report processing section 124 within a genotype report processing section 111; a falsely described population name report processing section 126 and an unexpected population name report processing section 127 within a population name report processing section 112; a multiple alleles report processing section 128, a blank missing report processing section 130 and an irregular blank character report processing section 132 within an allele number report processing section 113; a monomorphism report processing section 114; an in/del report processing section 115; a dual site reaction report processing section 116; a plural populations report processing section 117; a contamination report processing section 118; a special individual report processing section 119; a missing individual report processing section 120; and a reported/corrected items display processing section 121.
Also, the input data format of LINKAGE can employ the sections used here consisting of: a symbol genotype report processing section 122 and an unexpected genotype report processing section 124 within a genotype report processing section 111; a multiple alleles report processing section 128, a blank missing report processing section 130 and an irregular blank character report processing section 132 within an allele number report processing section 113; a monomorphism report processing section 114; an in/del report processing section 115; a dual site reaction report processing section 116; a plural populations report processing section 117; a contamination report processing section 118; a special individual report processing section 119; a missing individual report processing section 120; and a reported/corrected items display processing section 121.
Herein, each type of error has been described using an error made at a single locus in a single individual, but can be also described in the same manner using errors made at plural loci in plural individuals. Specifically, as an example, only a single individual (P07) having many missing data is described in
Herein, the whole sample population has been checked in a lump using the monomorphism report processing section 114 or the plural populations report processing section 117, but each population may be checked differently instead. Specifically, using the monomorphism report processing section 114, for example, it may be checked as such a case if there is a locus which may be polymorphic in the healthy population, but is not polymorphic in the patient population.
The data input support system for gene analysis according to the present invention has been described hereinbefore by means of specific embodiments, but the present invention is not limited thereto. Those skilled in the art could make various alterations or modifications in the constitutions and functions of the invention which may be associated with the foregoing or other embodiments, within the gist of the present invention.
The data input support system for gene analysis according to the present invention is available on a computer comprising memory means, input means, display means and the like, wherein information processing consisting of detection and display of certain types of errors in the input data of genotypes can be actually achieved by use of hardware resources such as memory means, input means and display means described above. Accordingly, the system applies to a technical idea utilizing natural laws, and can be industrially utilized in medical and/or biological research institutions and the likes which are engaged in linkage disequilibrium analysis.
Number | Date | Country | Kind |
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2005-323401 | Nov 2005 | JP | national |
This application is a Continuation of U.S. application Ser. No. 11/593,171 filed on Nov. 6, 2006. Priority is claimed based on U.S. application Ser. No. 11/593,171 filed on Nov. 6, 2006, which claims priority to Japanese Patent Application No. 2005-323401, filed on Nov. 8, 2005, all of which is incorporated by reference.
Number | Date | Country | |
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Parent | 11593171 | Nov 2006 | US |
Child | 12458222 | US |