The 5alpha-Reductase Type 1, But Not Type 2, Gene Is Expressed in Anagen Hairs Plucked from the Vertex Area of the Scalp of Hirsute Women and Normal Individuals

The study examined the expression of 5alpha-reductase type 1 (SDR5A1) and type 2 (SDR5A2) genes in the scalp hairs of 33 hirsute women (20 with polycystic ovary syndrome and 13 with idiopathic hirsutism), 10 men, and 15 normal women. Using RT-PCR, the researchers found that SDR5A2 was not expressed in any hair samples, and there were no significant differences in SDR5A1 expression among men, normal women, and hirsute women with or without polycystic ovary syndrome. The study concluded that SDR5A1 expression in the vertex area of the scalp does not contribute to the differences in hair growth seen between normal and hirsute individuals, suggesting that SDR5A1 is not the key enzyme affecting local androgen metabolism in scalp skin. The absence of SDR5A2 expression in the samples indicates that it may play a more significant role in hair growth and related conditions.