To determine the contribution of androgens to
the formation of male-gender identity, we studied male pseudohermaphrodites
who had decreased dihydrotestosterone production due to 5 alpha-reductase
deficiency.
These subjects were born with
female-appearing external genitalia and were raised as girls. They have plasma
testosterone levels in the high normal range, show an excellent response to
testosterone and are unique models for evaluating the effect of testosterone,
as compared with a female upbringing, in determining gender identity.
Eighteen of 38 affected subjects were
unambiguously raised as girls, yet during or after puberty, 17 of 18 changed
to a male-gender identity and 16 of 18 to a male-gender role.
Thus, exposure of the brain to normal levels
of testosterone in utero, neonatally and at puberty appears to contribute
substantially to the formation of male-gender identity.
These subjects demonstrate that in the
absence of sociocultural factors that could interrupt the natural sequence of
events, the effect of testosterone predominates, over-riding the effect of
rearing as girls.
Citation:
N Engl J Med 1979; 300: 1233–1237.
