Background/aims: To investigate the possible influence of TNF-α gene promoter polymorphisms in conferring a predisposition to PBC patients.
Methodology: We performed a meta-analysis of nine articles searched from PubMed up to July 2010 that investigated the association between two TNF-α polymorphisms (-308 and -238) and PBC.
Results: The data showed no significant association between TNF-α-308, -238 gene polymorphisms and the susceptibility to PBC in the global group (OR=0.95, 95%CI=0.80-1.13, p=0.55; OR=1.00, 95%CI=0.65-1.55, p=0.99, respectively). Stratified by sub-groups (European, American, Asian), TNF -308 minor allele, but not -238, was found to be a protective factor in the European population (OR= 0.81, 95%CI=0.67-0.99, p=0.04; OR=0.99, 95%CI=0.55-1.77, p=0.97, respectively). Moreover, no significant difference was observed between TNF-α-308 alleles and PBC when stratified by histological stages (stages I-II, OR=0.68, 95%CI=0.32-1.48, p=0.33; stages III-IV, OR=0.69, 95%CI=0.41-1.15, p=0.15).
Conclusions: TNF-α promoter polymorphisms might not be associated with PBC risk. However, studies with larger population of varying ethnicity and stratified by clinical and laboratory characteristics are needed to validate our findings.