Association between transforming growth factor-α polymorphism and ankylosing spondylitis: a meta-analysis update.
OBJECTIVE
The reported results of the relationship between genetic polymorphisms of tumor necrosis factor (TNF)-α -238, -308 locus and ankylosing spondylitis (AS) susceptibility are not always consistent. This article aims to perform a meta-analysis to collect all the relevant studies to date to further clarify the relationship between those genetic polymorphisms and AS.


METHODS
A computer search was carried out up to September 2011 for literature pertaining to AS and TNF-α polymorphisms.


RESULTS
Twenty-two articles were included, with 2,506 cases of AS and 3,023 normal controls. We searched for genotypes A allele vs. G allele, AA vs. GG + GA, and GA + AA vs. GG in a fixed/random-effects model. The effect summary odds ratios (ORs) and 95 % confidence intervals (CIs) were obtained, which shows there was no association between genetic polymorphisms and AS. As the heterogeneity was observed, in a subgroup analysis by ethnicity, the degree of risk of two genes with AS susceptibility was similar in populations of European and Asian origin. For the human leukocyte antigen (HLA)-B27+ population, results were not statistically significant.


CONCLUSIONS
ORs of various comparisons indicate that there is no association between TNF-α -238, -308 polymorphisms and AS susceptibility in the overall population and in the subgroup of Asian and non-Asian descent.
Epidemiology and Biostatistics School of Public Health, Anhui Medical University, Hefei 230032, China. smbzfdbxsandy@sina.com
Chencheng
C
Wang
Hong
H
Su
Weiwei
W
Chang
Zhiwei
Z
Xu
Qin
Q
Han
Xiaowei
X
Shan
D000483:Alleles; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D013167:Spondylitis, Ankylosing / Q000235:genetics*; D016211:Transforming Growth Factor alpha / Q000235:genetics*
D016211:Transforming Growth Factor alpha