Complete androgen insensitivity syndrome. Molecular characterization in two Chinese women.

OBJECTIVE

To study the molecular basis of complete androgen insensitivity syndrome (AIS).

STUDY DESIGN

The coding region of the human androgen receptor (hAR) gene in two women with AIS was amplified with polymerase chain reaction using 12 pairs of oligonucleotide primers and then sequenced with a dye terminator method.

RESULTS

Both patients had mutation in exon E of the androgen-binding domain. In one patient, codon 732 GAC (aspartic acid) was changed to ACC (asparagine), and her CAG polyglutamine tract had 27 repeats. In the other patient, codon 765 GCC (alanine) was changed to ACC (threonine), and her CAG polyglutamine tract in exon A had 19 repeats.

CONCLUSION

Except for CAG polyglutamine polymorphism, these two missense mutations were the only differences detected in the coding region of the hAR gene. Both mutations involved the CpG sequence, which has been regarded as a mutation hotspot. To the best of our knowledge, these two mutations have not been observed before in Chinese women. Elucidation of the molecular defects of AIS patients would be very helpful for genetic counseling and prenatal diagnosis.