Abstract 17

The Androgen Insensibility Syndrome is the most frequent cause of male pseudohermaphroditism. This X-linked disorder arises from a failure in the androgen receptor (AR) in the target cells. The gene is placed in the pericentromeric region of X in Xq12-q13. It is a gene made up of 8 exons and the most frequent anomalies in it are punctual mutations in the codifying regions. We showed the molecular analysis made to 9 patients with XY kariotype: 6 of them have partial androgen insensibility syndrome and different degrees of masculinization (PAIS) and the last 3 patients have complete androgen insensibility syndrome (CAIS). The genic amplification through PCR (Polymerase Chain Reaction) of the 8 exons was performed and no microdeletions were found in any of the cases. Study of the sequences of each exon by sequentiation allowed us to detect the following mutations: among the 6 patients with PAIS, 4 individuals of the same family (2 brothers and 2 maternal uncles) had a A596T mutation confirming the link to X-chromosome, the presence of the mutation in the mother. The others two sisters showed the R855H mutation. Among the patients with CAIS a Q153X mutation was detected in a girl. In the 2 other patients we could not find any mutations in the exons (1 to 8) studied and we still could find any mutation in promoter regions or sequences that could regulate the AR gene. In conclusion, the presence of mutations is responsible of the AR defects and the phenotype of the patients. Finally, this is first time that Q153X mutation is described in the literature and the directed mutagenesis should be done in order to know the binding ability of the R synthesized by this anormalous gene.