Role of a CYP17 polymorphism in the regulation of circulating dehydroepiandrosterone sulfate levels in women with polycystic ovary syndrome.

We studied 259 consecutive unselected white patients with the polycystic ovary syndrome (PCOS) and 161 matched controls for a common polymorphism of CYP17, the gene encoding for P450c17alpha, and did not observe an important modulatory effect of this variant on circulating DHEAS. It does not appear that this common variant of CYP17, a T to C substitution in the 5' promoter region, plays a significant role in the adrenal androgen excess of PCOS.