These are individuals which are genotypically male with a 46XY karyotype, but phenotypically are female. The condition results from a complete or partial absence of cytoplasmic receptors for testosterone in target tissues. It is an X-linked disorder with an incidence of 1 in 62000 male births.
The feminisation is a consequence of increased testicular secretion of oestradiol and from peripheral conversion of androgens to oestradiol. Serum LH and FSH are elevated as testosterone is ineffective at the hypothalamus.
Last reviewed 01/2018