Gene copy number variations of BCL2L11 and IL7R in differently progressing patients with chronic HBV infection

Objective To detect the copy numbers of the BCL2-like 11 apoptosis facilitator (BCL2L11) gene and the cytokine interleukin 7 receptor (IL7R) gene in patients with chronic hepatitis B virus (HBV) infection, and determine the relation between copy number variants (CNVs) and differential disease progression.Methods Study participants were recruited from the hospital setting from June 2006 to December 2008, and included four groups composed of uninfected healthy controls (n=20) , chronic HBV carriers (n=18) , chronic severe hepatitis patients (n=32) , and patients with HBV-associated hepatocellular carcinoma (HCC;n=18) .Patient DNA was extracted from peripheral blood and applied as template to TaqMan real-time PCR to measure gene copy numbers of BCL2L11 and IL7R.Results The BCL2L11 gene copy number was significantly different among the four groups (P<0.05) .In contrast, the IL7R gene copy number was not significantly different among the four groups P>0.05) .The BCL2L11 gene copy number was significantly lower in the HCC group compared to the other three groups (P<0.05) , while the chronic severe hepatitis group, HBV carrier group, and control group showed statistically similar gene copy numbers (P>0.05) .Conclusion CNVs of BCL2L11 exist in HBV-infected patients with different levels of liver damage.Future studies should address the contributions of these CNVs to the degree of liver inflammation during chronic HBV infection.