The following variables were found to be associated with liver fibrosis presence in univariate analysis: age (p = 0.005), BMI higher than 30 kg/m2 (p = 0.001), type 2 diabetes mellitus (p ≤ 0.001), AST (p ≤ 0.001), ALT (p ≤ 0.001), GGT (p = 0.023), triglycerides (p = 0.008) and A-allele from rs1047891 SNP (p = 0.036). The gene discussed is GPT; the disease is diabetes mellitus.