Insulin gene polymorphism and premature male pattern baldness in the general population.

Insulin is found in hair follicles and may play a role in the regulation of androgen metabolism and the hair growth cycle, which are relevant to the loss of scalp hair known as male pattern baldness. An excess of dihydrotestosterone on balding scalp indicates that the condition is androgen dependent. Premature male pattern baldness may be the male phenotype of familial polycystic ovary syndrome, a condition characterized by high levels of androgens and insulin that has been linked to insulin gene polymorphism. Therefore, we studied possible associations between relevant insulin gene polymorphisms and premature male pattern baldness in the general community. We examined the distribution of three dimorphic restriction fragment length polymorphisms: HphI, PstI and FokI in cases consisting of 56 men aged 18-30 years with significant baldness, and in 107 control men aged 50 years or more with no indication of baldness. No significant differences between cases and controls in allele, genotype or haplotype frequencies were identified. We conclude that, in the general population, the insulin gene is not associated with premature male pattern baldness.