Association of genetic polymorphism of low-density lipoprotein receptor with chronic viral hepatitis C infection in Han Chinese

To study the association between the Ava II polymorphism at the low-density lipoprotein receptor (LDL-R) gene exon 13 locus and chronic hepatitis C virus (HCV) infection in the Han Chinese, 84 chronic HCV-infected patients without anti-viral treatment, and 72 healthy blood donors were studied. Polymerase chain reaction combined with restriction fragment length polymorphism (PCR-RFLP) was used to detect the Ava II polymorphism at the LDL-R gene exon 13 locus. The comparisons of genotype distribution and allele frequency between chronic HCV-infected patients and healthy controls showed statistically significant differences (P = 0.045 and P = 0.036, respectively). Additionally, the minor allele frequency (MAF) C in the healthy controls was higher than that in the chronic HCV-infected patients group. There was no significant difference (P = 0.130) when the genotype distribution was compared between chronic HCV-infected patients with HCV viremia and those without HCV viremia. However, the comparisons of allele frequency between the two groups showed a statistically significant difference (P = 0.047), and the MAF C in HCV RNA negative group was significantly higher than that in HCV RNA positive group. There were no significant differences in genotype distribution and allele frequency of the Ava II restriction site at the LDL-R gene exon 13 locus between patients with chronic HCV infection and those with HCV-associated cirrhosis as well as between patients with normal serum alanine aminotransferase (ALT) and those with abnormal ALT levels. These results suggest that the Han Chinese have Ava II polymorphism at the LDL-R gene exon 13 locus. The Ava II polymorphism at the LDL-R gene exon 13 locus showed a statistically significant difference between chronic HCV-infected patients and healthy controls, indicating a significant contribution of the Ava II polymorphism in susceptibility to HCV infection in these patients. The MAF C in HCV RNA negative group was higher than that in HCV RNA positive group, suggesting that the Ava II polymorphism might also be associated with viremia in patients with HCV infection.