[Expression of androgen receptor gene in normal subjects and patients with complete androgen insensitivity]

The Androgen Receptor (AR) mRNA was studied in cultured cells from normal subjects and 10 patients with Complete (CAI, 9 patients, 5: R-, 4: R+) or Partial (PAI, 1 patient) Androgen Insensitivity. The probe was a 3,4 cDNA coding for the entire AR. AR mRNA appears as a 10 kb band. It is strongly expressed in genital skin fibroblasts, 50 to 100 times less in non genital skin. In genital skin fibroblasts, a 3 to 5 fold increase is observed after 1 h of treatment of the cultures with dihydrotestosterone (DHT, 5 nM) whereas a 22 fold decrease is observed after 24 h. A 3 fold increase is also observed after 1 h of treatment with progesterone (50 nM) or cyproterone acetate (500 nM) which does not seem to act as an antiandrogen in this model. The 10 kb band was present in all 10 A1 patients studied, though expressed at a much lower level. It is therefore possible that an abnormal regulation of the AR gene expression is involved in the mechanism of Androgen Insensitivity.