Differential Effects of Genetic Polymorphism on Comorbid Disease in Metabolic Dysfunction–Associated Steatotic Liver Disease

PNPLA3 rs738409, TM6SF2 rs58542926, and HSD17B13 rs72613567 have been associated with an increased risk of liver-related events (LRE) in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). In this study, we investigated the combined effects of these variants on LRE.The longitudinal multicenter cohort study enrolled 1178 patients with biopsy-proven MASLD. We calculated the genetic risk of hepatic fibrosis and LRE according to the impact of these variants.Patients with genetic fibrosis scores of 2, 3, and 4 or 5 were at greater risk than were patients with scores of 0 or 1, with odds ratios of 2.45 (95% confidence interval [CI] 1.27-4.74), 2.14 (95% CI 1.17-3.94), and 2.54 (95% CI 1.35-4.77), respectively. Multivariate analysis revealed that PNPLA3 and TM6SF2, but not HSD17B13, were significantly associated with LRE development. The hazard ratio (HR) of the genetic high-risk group for LRE was 1.91 (95% CI 1.20-3.04). The higher risk of LRE development in the genetic high-risk group was also seen in patients with F ≥ 3 or FIB-4 index > 2.67. The HRs of the genetic high-risk group for LRE were greater in patients without obesity, without diabetes, and of younger age compared with patients with obesity, with diabetes, or of older age, respectively.This combination of MASLD-related genetic variants is useful for predicting LRE in Japanese patients with MASLD. The genetic risk according to these variants is useful for LRE risk assessment, especially in patients without metabolic risk factors or in younger patients in Japan.