A novel androgen receptor gene mutation in a Chinese patient with complete androgen insensitivity syndrome

Abstract 

Objective

To identify the underlying androgen receptor gene mutation in a Chinese patient with typical symptoms of complete androgen insensitivity syndrome.

Study design

A Chinese female phenotype with 46, XY karyotype was diagnosed because of primary amenorrhea. Mutations were determined by polymerase chain reaction followed by DNA sequencing.

Results

DNA sequencing of the androgen receptor gene showed a G2439T transition causing E442X mutation in exon 1 in the patient with complete androgen insensitivity syndrome. The E442X mutation was a new de novo non-sense mutation in exon 1 of the androgen receptor gene. This non-sense mutation is located in the N-terminal transactivation domain and leads to a predicted truncated protein of 441 amino acids with loss of the end part of the N-terminal transactivation domain, and the DNA-binding and ligand-binding domain.

Conclusion

This E442X non-sense point mutation has not been described previously in cases of androgen insensitivity syndrome, and could lead to the synthesis of a short truncated non-functional androgen receptor probably responsible for the phenotype of complete androgen insensitivity syndrome in the affected individual. Gonadectomy should be planned to eliminate the risk of gonadal malignancy.

Keywords: Androgen receptor, Gene mutation, Androgen insensitivity syndrome