Association of TM6SF2 rs58542926 with Hepatic and Extrahepatic Alterations in Chronic Hepatitis C Patients

Abstract Human genetic variants play major roles in predicting and prognosis of several diseases. The effect of rs58542926 variant in transmembrane 6 superfamily member 2 (TM6SF2) gene on liver fibrosis among patients with chronic hepatitis C (CHC) is still debatable. The aim of this study is to investigate the possible effects of this variant in CHC patients. The study comprised 351 subjects: 250 CHC patients with different fibrosis stages (F0-F4) and 101 healthy volunteers. TM6SF2 (rs58542926) genotype was determined for all subjects. Blood samples were collected for complete blood count and biochemical analysis and cohort subjects were genotyped for the variant TM6SF2 rs58542926. Fibrosis staging was performed using Fibrotest and Fibroscan standard tests. The presence of the minor allele was significantly associated with severe liver fibrosis, as well as thrombocytopenia as an extrahepatic alteration. In addition, there was a significant association between the minor allele and lower thrombopoietin levels. The association of TM6SF2 genotype with thrombocytopenia was explored by measuring plasma thrombopoietin (TPO) levels for CHC patients. The results showed an association with extrahepatic alteration (thrombocytopenia) through its effect on plasma TPO level, and consequently on platelets production, which raises questions about the role of this variant in HCV treatment outcome. In conclusion, the occurrence of the minor allele of the variant rs58542926 can be linked to severe fibrosis stages as well as thrombocytopenia, enabling this variant to be used as a diagnostic pharmacogenetic marker for predicting the risk of fibrosis onset in CHC patients.