zum Thema Geschlechtsinkongruenz (der neue Begriff für Transsexualität, wie ich hier im Blog schon berichtete) veröffentlicht:
- „Gender incongruence and the brain – Behavioral and neural correlates of voice gender perception in transgender people“ (pubmed abstract hier)
- „Brain functional connectivity patterns in children and adolescents with gender dysphoria: Sex-atypical or not?“ (pubmed abstract hier)Die neurobiologische Sichtweise von Geschlechtsinkongruenz setzt sich seit der internationalen, interdisziplinären Konferenz von Frankfurt (2016) anscheinend immer mehr durch.
Wer sich dazu in deutscher Sprache informieren will, sei auf den Aufsatz von Dr. C. Haupt verwiesen, der ebenfalls nun mit Genehmigung des Verlags online abrufbar ist (in deutscher Sprache).
- „Biological origins of sexual orientation and gender identity: Impact on health.“ ebenfalls als abstract bei pubmed hier zu finden
Update: Hier eine Studie mit größerer Teilnehmerzahl und Details zu den Estrogen-Rezeptoren: „Molecular basis of Gender Dysphoria: androgen and estrogen receptor interaction“ – Ergebnis: „Our data show that ERβ plays a key role in the typical brain differentiation of humans.“
Update 11/2018: einen Überblick über die biologische Vielfalt beim Thema Geschlecht gibt es in englischer Sprache nun hier in der National Geographic:
Another intersex trait occurs in an isolated region of the Dominican Republic; it is sometimes referred to disparagingly as guevedoce—“penis at 12.” It was first formally studied in the 1970s by Julianne Imperato-McGinley, an endocrinologist from the Weill Cornell Medical College in New York, who had heard about a cohort of these children in the village of Las Salinas. Imperato-McGinley knew that ordinarily, at around eight weeks gestational age, an enzyme in male embryos converts testosterone into the potent hormone DHT. When DHT is present, the embryonic structure called a tubercle grows into a penis; when it’s absent, the tubercle becomes a clitoris. Embryos with this condition, Imperato-McGinley revealed, lack the enzyme that converts testosterone to DHT, so they are born with genitals that appear female. They are raised as girls. Some think of themselves as typical girls; others sense that something is different, though they’re not sure what.
But the second phase of masculinization, which happens at puberty, requires no DHT, only a high level of testosterone, which these children produce at normal levels. They have a surge of it at about age 12, just as most boys do, and experience the changes that will turn them into men (although they’re generally infertile): Their voices deepen, muscles develop, facial and body hair appear. And in their case, what had at first seemed to be a clitoris grows into a penis.
When Imperato-McGinley first went to the Dominican Republic, she told me, newly sprouted males were suspect and had to prove themselves more emphatically than other boys did, with impromptu rituals involving blades, before they were accepted as real men. Today these children are generally identified at birth, since parents have learned to look more carefully at newborns’ genitals. But they are often raised as girls anyway.