The role of CDKN2B in cardiovascular risk in ethnic Saudi Arabs: A validation study.

BACKGROUND: Genome-wide association studies (GWASs) have yielded a wealth of information furnishing support for the variability in genetic predisposition to disease. However, the actual impact of such findings on any particular ethnic population needs to be validated through replication studies. In the present study, we verified recent findings of a GWAS demonstrating a strong association for the cyclin-dependent kinase 4 inhibitor B (CDKN2B) genomic region with coronary artery disease (CAD)/myocardial infarction (MI) in ethnic Saudi Arabs. METHODOLOGY: We genotyped 8 CDKN2B SNPs for cardiovascular risk in 4650 Saudi Arabs, comprising 2429 CAD cases (1860 males; 569 female) and 2221 controls (1189 male; 1032 female) by Taqman assay. RESULTS: Four SNPs, rs4977574_A [0.56(0.50-0.63); p < 0.0001], rs10757274_A [0.87(0.77-0.97); p = 0.014], rs10738607_A [0.89(0.80-1.00); p = 0.043] and rs1333045_T [0.54(0.48-0.61); p < 0.0001] residing on the CDKN2B gene were significantly associated with CAD following multivariate adjustments for MI, HTN and DM, while four others were weakly associated with the disease. Likewise, three SNPs, rs1412829_G [0.84(0.72-0.97); p = 0.019], rs564398_C [0.81(0.70-0.94); p = 0.006], rs4977756_G [0.87(0.76-0.99); p = 0.036] were significantly associated with MI after multivariate adjustments for CAD, HTN and DM, while the other five displayed borderline associations. CONCLUSIONS: Our findings strongly support the notion of a critical role for the CDKN2B gene locus as a cardiovascular risk in ethnic Arabs. The study also demonstrates the importance of replication studies in ascertaining the role of a genomic sequence in disease.