BACKGROUND & AIMS: Carriage of rs738409:G in patatin-like phospholipase domain-containing 3 (PNPLA3) is associated with an increased risk for developing alcohol-related cirrhosis and hepatocellular carcinoma (HCC). Recently, rs72613567:TA in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13) was shown to be associated with a reduced risk for developing alcohol-related liver disease and to attenuate the risk associated with PNPLA3 rs738409:G. This study explores the risk-associations between these two genetic variants and the development of alcohol-related cirrhosis and HCC. APPROACH AND RESULTS: Variants in HSD17B13 and PNPLA3 were genotyped in 6,171 participants, including: 1,031 with alcohol-related cirrhosis and HCC; 1,653 with alcohol-related cirrhosis without HCC; 2,588 alcohol misusers with no liver disease; and 899 healthy controls. Genetic associations with the risks for alcohol-related cirrhosis and HCC were determined using logistic regression analysis. Carriage of HSD17B13 rs72613567:TA was associated with a lower risk for both cirrhosis (OR 0.79 [95% CI 0.72-0.88], p=8.13×10-6) and HCC (OR 0.77 [95% CI 0.68-0.89], p=2.27×10-4), while carriage of PNPLA3 rs738409:G was associated with an increased risk for developing cirrhosis (OR 1.70 [95% CI 1.54-1.88], p=1.52x10-26) and HCC (OR 1.77 [95% CI 1.58-1.98], p=2.31×10-23). These associations remained significant after adjusting for age, sex, body mass index, type II diabetes mellitus and country. Carriage of HSD17B13 rs72613567:TA attenuated the risk for developing cirrhosis associated with PNPLA3 rs738409:G in both men and women but the protective effect against the subsequent development of HCC was only observed in men (p=1.72×10-4; ORallelic, 0.75; 95% CI, 0.64-0.87). CONCLUSIONS: Carriage of variants in PNPLA3 and HSD17B13 differentially affect the risk for developing advanced alcohol-related liver disease. A genotypic/phenotypic risk score might facilitate earlier diagnosis of HCC in this population
