Background
Osteoarthritis (OA) is a common chronic disease of the joints. Genetic factors may play a role in its development, and polymorphisms in the estrogen receptor alpha gene ( ERα ) have been associated with OA. However, previous studies into this relationship have reported inconsistent results, so we aimed to systematically review the association between ERα polymorphisms and OA susceptibility.
Methods
We conducted a comprehensive literature search of Ovid MEDLINE, EMBASE, CBM, and PubMed databases, and Google scholar, and identified 11 eligible studies that examined the association between ERα polymorphisms and OA susceptibility. We carried out a meta-analysis of these studies based on ERα Xba I (rs9340799) and Pvu II (rs2234693) genotypes.
Results
Seventeen comparisons involving 10 European and seven Asian populations of 5,325 OA patients and 10,834 controls were included in the study. The ERα Xba I polymorphism were significantly associated with OA in Europeans (AA vs. AG + GG: OR = 1.17, 95% confidence interval (CI) = 1.02–1.34, P = 0.03; AG vs. AA + GG: OR = 0.86, 95% CI = 0.75–0.99, P = 0.04) but not in Asian populations. No association was found between OA and the ERα Pvu II polymorphism in any population (C vs. T, OR = 0.98, 95% CI = 0.93–1.03, P = 0.37; CC vs. TT + CT, OR = 0.97, 95% CI = 0.89–1.06, P = 0.55; CT vs. CC + TT, OR = 0.99, 95% CI = 0.92–1.06, P = 0.75; TT vs. CC + CT, OR = 1.01, 95% CI =0.92–1.12, P = 0.79).
Conclusions
This study suggested that there may be a weak relationship between the ERα Xba I polymorphism and OA in Europeans but not Asians, and that the ERα Pvu II polymorphism was not associated with OA in either population. However, large well-designed studies are necessary to confirm these results in more homogeneous populations.