Background: Tasting compounds as bitter is genetically determined. Phenylthiocarbamide (PTC) tastes bitter to some or tasteless to others and has been linked to food preference. The bitter taste response for PTC is mediated by TAS2R38 gene and three groups of tasters have been found, none, medium and super tasters. Individuals who taste PTC as bitter drink less alcohol compared to PTC non-tasters. A concern for selecting patients for a liver transplant is the likelihood of relapse of alcohol use. Increased efforts to identify patients at high risk of relapse may improve patient outcomes. We studied PTC taste perception and TAS2R38 genotype as a possible marker of risk for alcohol use in liver transplant patients.Methods and Procedures: Both pre and post liver transplant patients over 18 years of age were included in the study. Demographic information (age, gender, race), etiology of liver disease, history of alcohol and tobacco use were gathered in a questionnaire. Taste sensitivity to PTC on a prepared paper strip with PTC was assessed on a scale of 0, 1 or 2, with 0 being tasteless, 1- very mildly bitter and 2 -extremely bitter. Buccal swabs were taken for genetic analysis for the TAS2R38 gene.Results: Sixty patients were studied .The male: female ratio was 40:20. Mean age of patients was 59 years (range 24-75 years). Of these 60 patients 36 were post-liver transplantation (33 from deceased and 3 from live donors).Nine patients had alcoholic liver disease. Of the 60 patients, 21 tasted the PTC as tasteless, 22 as mildly bitter and 17 as very bitter. Among the patients with ARLD, non tasters were 3, intermediate tasters 2 and super tasters 4.Further analysis suggests that among PTC non-tasters there is a higher chance of liking alcohol (12 vs. 9). Also among those who tasted PTC as mildly bitter/very bitter (can be grouped as tasters together) more patients DID NOT consume alcohol (29 vs. 10). This relationship is not clear for smoking.

Conclusion: Patients who taste PTC (as mildly or very bitter) are less likely to consume alcohol, especially in significant quantities compared to non-tasters. Hence it can be concluded that ‘tasters’ have a less chance of having problems with alcohol pre or post transplantation. Recidivism analysis and genetic testing is ongoing.

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