One person we studied had untreated male gender dysphoria (S7), took no hormones and kept his transsexual feelings under wraps. He appeared to have a large INAH3 volume - in the male range - but a female INAH3 number of neurons (68) and a female BSTc somatostatin neuron number (95). Hence, this individual's hypothalamic characteristics were mid-way between male and female valuesBiology is fuzzy: there are degrees of masculinisation and feminisation in various neuro-anatomical structures. This data suggests that the degree has a correlation with intensity of transsexuality, whether the patient transitions early, late, or not at all.
68. Garcia-Falgueras A, Swaab DF. A sex difference in the hypothamaic uncinate nucleus: relationship to gender identity. Brain 2008;131:3132-3146
95. Kruijver FP, Zhou JN, Pool CW, Hofman MA, Gooren LJ, Swaab DF. Male-to-female transsexuals have female neuron numbers in a limbic nucleus. J Clin Endocrinol Metab 2000;85:2034-2041
Monday, 21 December 2009
Sexual differentiation of the human brain in relation to gender identity and sexual orientation D.Swaab & A.Garcia-Fulgaras Functional Neurology, Jan-Mar 2009: