Rare medical conditions affecting foetal testosterone project
Whereas one of our projects is measuring fetal testosterone and other sex steroids in amniotic fluid, via amniocentesis, in a longitudinal follow-up design, this project is testing for associations between fetal testosterone levels and number of autistic traits using carefully selected medical conditions in which fetal sex steroid levels are abnormally high or low. Examples include Congenital Adrenal Hyperplasia (CAH) who for genetic reasons have over-production of foetal testosterone; and Androgen Insensitivity Syndrome (AIS) who for genetic reasons have some or all of their androgen receptors missing, so cannot bind the testosterone they produce. We found that girls with CAH are masculinized in terms of their AQ (Autism Spectrum Quotient) score, relative to their unaffected sisters. We are predicting that males with AIS will be feminized in terms of their AQ score, and this study is underway. We have also studied genetic females who have had a sex change (female-to-male transsexuals) because they have masculinized 2D:4D ratios, taken as a proxy for elevated fetal testosterone levels.