Association between the European GWAS-identified susceptibility locus at chromosome 4p16 and the risk of atrial septal defect: a case-control study in Southwest China and a meta-analysis.

Atrial septal defect (ASD) is the third most frequent type of congenital heart anomaly, featuring shunting of blood between the two atria. Gene-environment interaction remains to be an acknowledged cause for ASD occurrence. A recent European genome-wide association study (GWAS) of congenital heart disease (CHD) identified 3 susceptibility SNPs at chromosome 4p16 associated with ASD: rs870142, rs16835979 and rs6824295. A Chinese-GWAS of CHD conducted in the corresponding period did not reveal the 3 susceptibility SNPs, but reported 2 different risk SNPs: rs2474937 and rs1531070. Therefore, we aimed to investigate the associations between the 3 European GWAS-identified susceptibility SNPs and ASD risk in the Han population in southwest China. Additionally, to increase the robustness of our current analysis, we conducted a meta-analysis combining published studies and our current case-control study. We performed association, linkage disequilibrium, and haplotype analysis among the 3 SNPs in 190 ASD cases and 225 age-, sex-, and ethnicity-matched healthy controls. Genotype and allele frequencies among the 3 SNPs showed statistically significant differences between the cases and controls. Our study found that individuals carrying the allele T of rs870142, the allele A of rs16835979, and the allele T of rs6824295 had a respective 50.1% (odds ratio (OR) = 1.501, 95% confidence interval (CI) = 1.122-2.009, PFDR-BH = 0.018), 48.5% (OR = 1.485, 95%CI = 1.109-1.987, PFDR-BH = 0.012), and 38.6% (OR = 1.386, 95%CI = 1.042-1.844, PFDR-BH = 0.025) increased risk to develop ASD than wild-type allele carriers in our study cohort. In the haplotype analysis, we identified a disease-risk haplotype (TAT) (OR = 1.540, 95%CI = 1.030-2.380, PFDR-BH = 0.016). Our meta-analysis also showed that the investigated SNP was associated with ASD risk (combined OR (95%CI) = 1.35 (1.24-1.46), P < 0.00001). Our study provides compelling evidence to motivate better understanding of the etiology of ASD.