Tumor necrosis factor-alpha-308 G/A polymorphism and acute liver graft rejection: a meta-analysis

Studies investigating the association between TNF-α-308 promoter polymorphism and acute rejection (AR) in liver transplant (LT) recipients report conflicting results. The objective of this study was to quantitatively summarize the evidence for such a relationship.

Two investigators independently searched the Medline and Embase databases. Data were extracted using standardized forms and odds ratios (OR) with 95% confidence intervals (CI) were calculated.

This meta-analysis included nine case-control studies and a cohort research, which included 1104 cases of LT recipients in which 351 cases developed AR and 753 cases did not develop AR. All control samples were in Hardy-Weinberg proportion. An association between AR and A allele was not found in the overall population (OR=1.35, 95% CI=0.83, 2.22). Regarding ethnic diversity, because only 1 study was performed in Asian patients, the result of subgroup analysis by ethnicity would not be reliable for Asians. The calculated OR for A allele and AR risk in LT recipients among Caucasians was 1.36 (95% CI=0.78, 2.36). The results for the AA/AG genotype vs GG genotype showed a similar trend to those for the A allele.

This meta-analysis suggests that TNF-α-308 promoter polymorphism may be not associated with AR in LT recipients among Caucasians. In future, additional studies based on Asian patients should be performed to evaluate the association between TNF-α-308 G/A polymorphism and AR risk in Asian population.