RET and PHOX2B genetic polymorphisms and Hirschsprung's disease susceptibility: a meta-analysis.

BACKGROUND: Many publications have evaluated the correlation between RET, PHOX2B polymorphisms and Hirschsprung's disease with conflicting results. We performed this meta-analysis to clarify the association of RET, PHOX2B polymorphisms with HSCR. METHODS: We searched Pubmed, Elsevier Science Direct, China National Knowledge Infrastructure database, Chinese Biomedical database, Google scholar. The combined odds ratio (OR) with 95% CI was calculated to estimate the strength of the association. Heterogeneity and publication bias were also assessed. RESULTS: In total, 16 studies concerning RET and 4 studies concerning PHOX2B were included in the meta-analysis. The effects of five polymorphisms of RET (rs1800858, rs1800860, rs1800861, rs10900297, rs2435357) and one polymorphism (rs28647582) of PHOX2B were evaluated. We found a significant correlation between RET polymorphisms and HSCR. For rs1800858, the overall ORs (95% CI) of the A versus G, AA versus GG, AA/AG versus GG and AA versus GG/AG were 3.81 (2.28-6.35); 8.36 (3.45-20.25); 3.59 (1.83-7.02); and 6.60 (3.66-11.89). For rs1800861, the comparison of subjects in the G versus T, GG versus TT, GG/TG versus TT and GG versus TT/TG were 2.85(1.81-4.47); 5.38(2.68-10.80); 3.07(2.17-4.34) and 4.14(1.84-9.30) respectively. For rs10900297, the comparison results showed statistically significant. (OR(C versus A) = 5.05,95%CI = 4.16-6.13; OR(CC versus AA) = 9.73, 95%CI = 5.94-15.94; OR(CC/AC versus AA) = 5.31, 95%CI = 3.27-6.82; OR(CC versus AC/AA) = 7.06,95%CI = 5.60-8.91.) But, for rs1800860, the GG/GA versus AA did not reach statistical association (OR = 3.77, 95% CI = 0.94-15.07) and the G versus A, GG versus AA, GG versus GA/AA were 2.23 (1.60-3.11);4.56 (1.14-18.27); 2.38 (1.66-3.43) respectively. For rs2435357, the T versus C, TT versus CC, TT/TC versus CC and TT versus CC/TC were 4.53 (3.27-6.27); 11.44 (5.67-23.10); 4.04 (2.92-5.57), and 9.01(5.25-15.46).The single polymorphism of PHOX2B gene wasn't related to the risk for HSCR. CONCLUSIONS: This meta-analysis shows a significant association between RET polymorphisms and HSCR.