Studies On The Relationship Between The Polymorphisms Of MTHFR, IL-28B And The Outcome Of HBV Infection

Hepatitis B virus (HBV) infection lead to a variety of clinical manifestions, including acute self-limited infection, asymptomatic carrier, chornic hepatitis, cirrhosis or hepatocellular carcinoma (HCC). Studies have shown that polymorphisms of the host genes play important roles in the disease development after HBV infection, and the results are various in different regions and ethnics. As a result, the analysis of the influence of methylenetetrahydrofolate reductase (MTHFR), Interleukin-28B (IL-28B) and disease progression after HBV infection in Tianjin may contribute to understanding the etiology of liver disease occurrence in this region.AIM:To investigate the correlation between MTHFR rs1801133, IL-28B rs8099917polymorphisms and the outcome of HBV infection. Further, through the analysis of total serum levels of HCY, MTHFR and folate to investigate the correlations of them and their influence on the outcome of patients affected by HBV.METHODS:Genotypes of rs1801133(C>T)in MTHFR and rs8099917(T>G) in IL-28B locus were determined by TaqMan SNP genotyping, MTHFR rs1801133from3060individuals (including704HBV-induced liver cirrhosis,726HBV-related HCC,442Chronic Hepatitis B,81asymptomatic carrier,558self-limited infector and549healthy people as control); While IL-28B rs8099917from486subjects (including100HBV-induced liver cirrhosis,99HBV-related HCC,143self-limited infector and144healthy people as control). Ninety patients (mached by gender, age and genotype from MTHFR SNP analysis, including30self-limited infectors,30HBV-induced liver cirrhosis and30HCC) were included in the further analysis of total serum levels of HCY, MTHFR and folate by ELISA.RESULTS:1.Of the3060subjects, the frequencies of the MTHFR rs1801133genotypes were TT29.3%,CT48.9%and CC21.8%,and the frequencies of allele T and C accounted for53.8%and46.2%, respectively. There was no significant difference among groups of the frequency of genotype or allele frequency(P>0.05). But in male patients with HCC,the frequence of T allele (49.8%) was lowest(P<0.05). The Logistic analysis (adjusted for gender and age) showed that TT genotype and T allele reduced the risk of HCC (adjusted OR and P) were(0.588,0.003;0.768,0.003; vs healthy control), and (0.598,0.01;0.772,0.01; vs the self-limited group). Analysis of the distribution of genotypes in different genders showed that TT males had a reduced the risk of HCC(0.587,0.017,vs healthy control; and0.470,0.002,vs self-limited group) and liver cirrhosis(0.624,0.046,vs self-limited), but TT females had no change in the risk of any group. In contrast, CT females had a reduced risk of HCC. The analysis of the distribution of alleles also showed that, T allele reduced the risk of liver cirrhosis and HCC in males, but not in females. Further, the analysis of correlation between clinical features and the genotypes showed that for males TT genotypes was decreased the risk of HBsAg(+) and reduce the level of AFP, while increased the risk of γ-GT Ⅱ (+) and child-pugh stage B and C for females.2. A significant trend was observed that homocysteine increased with the impairment of liver function. The levels of serum MTHFR and folate were significantly higher in self-limited patients than in HBV-related liver cirrhosis and HCC. Serological assay showed there was a significant correlation between MTHFR and folate. Furthermore, the analysis of the plasma levels of these parameters showed that drinking was strongly associated with the high level of HCY in male patients with liver cirrhosis or HCC. The levels of serum MTHFR and folate decreased in HBsAg-positive patients with HBV DNA(≧500copies/ml).3. The distribution of genotype and allele of the rs8099917locus were in accordance with Hardy-Weinberg equilibrium in different groups or total population. The frequencies of the rs8099917TT, GT, GG genotypes were89.3%,10.5%and0.2%, and the frequency of allele T and G accounted for94.5%and5.5%,respectively. In respect of genotype or allele frequency there was no significant difference among groups(P>0.05), and in the multinomial logistic analysis, comparing to TT genotype, the ORs and(95%CI)of TG/GG genotypes were1.589(0.735～3.437),1.351(0.550～3.316)and1.704(0.717～4.052), respectively. The analysis of genotype frequencies in different groups with different clinical features showed that TG/GG genotypes significantly increased the risk of γ-GT±(+) for individuals with HBV-related HCC(χ2=17.534, P=0.001),with OR14.821(3.227～68.064), especially for males(χ2=14.924, P=0.014),with OR(95%CI)as45.000(2.772～730.571).CONCLUSION:1.MTHFR rs1801133TT genotype and T allele may reduce the risk of HCC in patients with HBV infection,especially for male,but not female.In contrast,CT genotype reduce the risk of HCC for female.2. For the HBV-infected male with drinking history, low levels of serum MTHFR and folate tend to increase the risk of liver malignance.3. IL-28B rs8099917SNP has no correlation with outcome of HBV infection.