UGT1A1 and hepatitis A virus infection: The gene allele frequency of UGT1A1 was significantly elevated in post-hepatitis hyperbilirubinemia patients compared with that in hepatitis-control patients (UGT1A1*28: 0.350 vs 0.143; UGT1A1*6: 0.286 vs 0.119; p < 0.05, Table 1).