An association between serum testosterone level and HLA phenotype.

The concentration of testosterone was determined in sera of 122 HLA-typed women. Subsequently the women were classified in the category below or above the mean serum testosterone concentration. When the frequencies of HLA antigens were compared in these two categories of women, it was found that HLA-B5 and HLA-B12 antigens were significantly increased in the category of women with serum testosterone level above the mean concentration (P less than 0.01 and P less than 0.05, respectively). The frequency of HLA-B8 antigen was significantly decreased in the same category of women (P less than 0.05). The comparisons of the mean testosterone values of each HLA antigen and the variance analysis have also shown significant differences between the mean of HLA-B8 antigen and the means of other HLA antigens--HLA-A2, A3, A9, B5, B12 and Bw35. These results gave further conclusive evidence that gene(s) inside HLA region influence either the androgen hormone metabolism itself or cellular sensitivity to hormonal action as it has been presented for congenital adrenal hyperplasia.