Association of genetic polymorphisms of chemokines and their receptors with clearance or persistence of hepatitis C virus infection

BACKGROUND

Polymorphisms of certain genes may have an effect on either persistence of infection or spontaneous clearance of hepatitis C virus (HCV). We hypothesized that one or more variants of chemokines (CCL2 and CCL5) and chemokine receptors (CC chemokine receptor type 2 [CCR2]) genes are associated with the susceptibility to HCV infection.

METHODS

We recruited 1460 patients with chronic HCV (CHC), 108 subjects with spontaneous virus clearance (SVC) and 1446 individuals as a healthy control group. All were genotyped for single nucleotide polymorphisms: rs13900 C/T of CCL2, rs3817655 T/A of CCL5 and rs743660 G/A and rs1799864 G/A of CCR2 using allelic discrimination real-time PCR technique.

RESULTS

The carriage of the A allele of CCR2 rs743660 was significantly higher in CHC compared to SVC (odds ratio [OR] 4.03) and to controls (1.42) and in controls compared to SVC (2.85) (all P < 0.01). Similarly, the A allele of CCR2 rs1799864 was significantly higher in the CHC group when compared with both SVC (1.97) and controls (2.13) (both P < 0.01), but the OR between controls and SVC was not significant (1.08, P = 0.723). Carriage of C allele of CCL2 rs13900 and the T allele of CCL5 rs3817655 were significantly higher in SVC group when compared with both CHC (OR = 0.19 and OR = 0.24, respectively) and control groups (OR = 0.65 and OR = 0.45, respectively [all P < 0.01]).

CONCLUSIONS

Susceptibility to HCV infection is associated with A alleles of both (rs743660 and rs1799864 G/A) of CCR2 while spontaneous clearance of HCV is associated with the C allele of rs13900 of CCL2 and T allele of rs3817655 of CCL5.

Associations of human leucocyte antigen class II-DQB1 alleles with hepatitis C virus infection in Egyptian population: a multicentre family-based study

Hepatitis C infection is a global pandemic. HLA-DQB1 alleles are believed to have an effective role in immune response against HCV including susceptibility to or protection from this infection. The aim of this study was to investigate the contribution of HLA-DQB1 alleles in the outcome of HCV genotype-4 infection through a family-based association study. Egyptian families with HCV (324) were recruited for this study (324 index positive for RNA-HCV, 225 positive relatives representing chronic hepatitis C cases and 582 family members negative for HCV-RNA [control], 63 of whom spontaneously cleared the virus. All subjects were genotyped for HLA-DQB1 alleles by sequence-specific primers (SSP-PCR) and sequence-based typing (SBT) methods. The frequency of DQB1*02:01:01 carriage was significantly higher in infected patients when compared to controls and those who spontaneously cleared virus (OR=5.47, P<.0001 and OR= 6.5234, P<.0001, respectively), and the carriage of the DQB1*03:01:01:01 allele was significantly higher in those who cleared and controls when compared to the infected patients (OR=0.2889, P<.0001 and OR=0.3016, P<.0001, respectively). On the other hand, the frequency of DQB1*06:01:01 and QB1*05:01:01:01 alleles was not associated with infection (comparison of infected and cleared patients showed OR of 2.1598 [P<.01]), but it becomes nonsignificant after adjustments with the Bonferroni formula (P_C >0.05) and OR= 1.3523, P>.05, respectively. This study shows that clearance of HCV is associated with DQB1*03:01:01:01 allele and chronicity of HCV infection associated with the risk allele: DQB1*02:01:01.