OBJECTIVES: We tested the hypothesis that a genetic deletion (Del) variant in the REPIN1 gene is associated with the severity of nonalcoholic fatty liver disease (NAFLD) in humans.METHODS: Sixty-three donors of liver biopsies from individuals with obesity and different degrees of NAFLD and fibrosis were screened for a Del REPIN1 gene variant and liver REPIN1 mRNA expression.RESULTS: In 8 homozygous Del carriers, we found significantly lower NAFLD activity and fibrosis scores compared with 55 wild-type allele carriers.DISCUSSION: A Del variant of REPIN1 may be associated with a lower risk of the development of NAFLD.