Background: Recent genome-wide studies have shown a significant association of a locus on chromosome 9p21.3 and coronary artery disease. We performed a case-control study to investigate the association between this locus and abdominal aortic aneurysm (AAA).
Methods and results: A total of 1714 patients (899 patients with AAA and 815 controls) were genotyped for the lead single-nucleotide polymorphism, rs1333049, on chromosome 9p21. The frequency of the C (risk) allele of rs1333049 in the control group was 0.471. There was a significant association between the C allele and AAA (odds ratio, 1.22; 95% confidence interval, 1.06 to 1.39; P=0.004). The genotypic-specific odds ratios (compared with the GG genotype) were 1.17 (95% confidence interval, 0.93 to 1.47; P=0.191) for the GC genotype and 1.50 (95% confidence interval, 1.14 to 1.97; P=0.004) for the CC genotype. In logistic regression modeling, the association of the CC genotype with AAA was independent of the presence of clinical coronary artery disease (odds ratio, 1.46; 95% confidence interval, 1.11 to 1.94; P=0.008).
Conclusions: Our study shows that the recently identified chromosome 9 variant that increases risk of coronary artery disease is also associated with the presence of AAA. The findings suggest that the effect of this locus on risk of cardiovascular disease extends beyond the coronary circulation.