Page ST et al. (2006) The androgen receptor gene CAG repeat polymorphism does not predict increased risk of heart disease: longitudinal results from the Massachusetts Male Ageing Study. Clin Endocrinol 65: 333–339

As heart disease is more prevalent in men than in women, a role for androgens has been proposed. Cardiovascular risk factors are thought to be associated with the number of cytosine–adenine–guanine (CAG) repeats in exon 1 of the androgen-receptor gene. Previous studies, however, have produced inconsistent results. Page et al. studied DNA sequence data from over 1,000 men who participated in the Massachusetts Male Aging Study, and found that the number of CAG repeats was not associated with the development of heart disease.

Cross-sectional and longitudinal analyses revealed no association between the number of CAG repeats and the development of heart disease; neither did they demonstrate any associations between the number of CAG repeats and cardiovascular risk factors such as BMI, waist-to-hip ratio, LDL level or HDL level.

As participants in the Massachusetts Male Aging Study were representative of the Boston population, 97% of the study participants were white. It is possible, therefore, that the number of CAG repeats might be associated with heart disease in different ethnic groups. It should also be noted that this analysis only had enough statistical power to detect differences of >15%, so smaller, but still significant, differences might have been missed.