A genome-wide association study reveals susceptibility loci for myocardial infarction/coronary artery disease in Saudi Arabs

- We performed GWAS for CAD/MI in 5431 Saudi Arabs by the Affymetrix Axiom Genotyping platform.
- We discovered SNPs in 14 loci conferring risk for CAD/MI.
- Results on 6 of these SNPs were replicated in an independent dataset.
- Our heritability estimations for CAD/MI were approximately 33% and 44%, respectively.
- Our study identified several susceptibility variants as well as currently unfamiliar genes for CAD/MI in ethnic Arabs.

BackgroundMultiple loci have been identified for coronary artery disease (CAD) by genome-wide association studies (GWAS), but no such studies on CAD incidence has been reported yet for any Middle Eastern population.MethodsIn this study, we performed a GWAS for CAD and myocardial infarction (MI) incidence in 5668 Saudis of Arab descent using the Affymetrix Axiom Genotyping platform.ResultsWe describe SNPs at 16 loci that showed significant (P < 5 × 10−8) or suggestive GWAS association (P < 1 × 10−5) with CAD or MI, in the ethnic Saudi Arab population. Among the four variants reaching GWAS significance in the present study, the rs10738607_G [0.78(0.71-0.85); p = 2.17E-08] in CDNK2A/B gene was associated with CAD. Two other SNPs on the same gene, rs10757274_G [0.79(0.73-0.86); p = 2.98E-08] and rs1333045_C [0.79(0.73-0.86); p = 1.15E-08] as well as the rs9982601_T [1.38(1.23-1.55); p = 3.49E-08] on KCNE2 were associated with MI. These variants have been previously described in other populations. Several SNPs, including the rs7421388 (PLCL1) and rs12541758 (TRPA1) displaying a suggestive GWAS association (P < 1 × 10−5) with CAD as well as rs41411047 (RNF13), rs32793 (PDZD2) and rs4739066 (YTHDF3), similarly showing weak association with MI, were confirmed in an independent dataset. Furthermore, our estimation of heritability of CAD and MI based on observed genome-wide sharing in unrelated Saudi Arabs was approximately 33% and 44%, respectively.ConclusionsOur study has identified susceptibility variants for CAD/MI in ethnic Arabs. These findings provide further insights into pathways contributing to the susceptibility for CAD and will enable more comprehensive genetic studies of these diseases in Middle East populations.