Phenotypic diversity in siblings with partial androgen insensitivity syndrome
- aDepartment of Child Health, University of Wales College of Medicine, Heath Park, Cardiff CF4 4XN, bDepartment of Paediatrics, University of Cambridge, Addenbrooke’s Hospital, Cambridge
- Dr Evans.
- Accepted 5 March 1997
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.