Alcohol usage over time results in a number of metabolic alterations including the production and secretion into the blood of increased quantities of pI 5.7 and 5.9 isoforms of transferrin. These transferrin isoforms (TIs) can be detected by isoelectric focusing and their quantities directly correlate with the amount of alcohol intake by an individual over a time period related to the turnover rate of transferrin in blood; the Tls diminish back to normal levels after alcohol intake is stopped. Thus, quantitation of the Tls is clinically useful for initial estimation of alcohol usage and for monitoring individuals under treatment for alcoholism disease. Present tests for TIs are cumbersome and time-consuming. We have discerned the probable molecular difference between the native transferrin and the TIs, and have prepared reagents that discern the molecular difference of the TIs. The purpose of this proposal is to construct quantitative assays for the Tls in serum specimens, validate the quantities of TIs with our assay system compared to the isoelectric focusing method, and to establish the clinical usefulness of the assay in the testing of individuals suffering from alcoholism as well as possible correlations with other parameters of compromised liver function. The assay will be cost effective and thus should find wider usage in the clinical management of alcoholism.