The relationship between tumour necrosis factor-α gene polymorphism and susceptibility and clearance of the persistent hepatitis B virus infection in a Chinese population: a meta-analysis

To date, many studies conducted in the Chinese population have determined the correlation between the tumour necrosis factor-α (TNF-α)-238G/A, -308G/A, -857C/T and -863C/A polymorphisms and persistent hepatitis B virus (HBV) infection. However, their results remain inconclusive. With the aim of confirming this correlation, we performed a meta-analysis of 19 studies. The dichotomous data are presented as the OR with a 95% CI. The results of our study indicate that carriers of the TNF-a-857T allele among the pooled Chinese population were more likely to show spontaneous clearance of HBV (T vs C: OR = 0.824, 95% CI = 0.713-0.953, p 0.009; TT vs CC: OR = 0.701, 95% CI = 0.507-0.970, p 0.032; TC vs CC: OR = 0.804, 95% CI = 0.683-0.947, p 0.009; TT + TC vs CC: OR = 0.835, 95% CI = 0.716-0.974, p 0.021). The TNF-a-308A allele was associated with significantly reduced persistent HBV infection risk in the Chinese (A vs G: OR = 0.585, 95% CI = 0.456-0.751, p 0.002; AG vs GG: OR = 0.519, 95% CI = 0.341-0.789, p <0.000; AA + AG vs GG: OR = 0.512, 95% CI = 0.339-0.772, p 0.001). Persistent HBV infection susceptibility is associated with the TNF-α-308G/A gene polymorphism in the Chinese population, whereas HBV clearance is associated with the TNF-α-857C/T gene polymorphism.