Transsexuality Among Twins: Identity Concordance, Transition, Rearing, and Orientation

  title={Transsexuality Among Twins: Identity Concordance, Transition, Rearing, and Orientation},
  author={Milton Diamond},
  journal={International Journal of Transgenderism},
  pages={24 - 38}
  • M. Diamond
  • Published 1 January 2013
  • Psychology
  • International Journal of Transgenderism
ABSTRACT The relative contributions of genetic and environmental factors to the development of gender identity have been debated. Twins were studied that are concordant or discordant for gender identity status in order to provide clarification of this issue. An extensive library search yielded reports of 27 male and 16 female sets concordant or discordant for transsexuality. An Internet bulletin board search and clinical contact requests for participants in a survey of twins in which one or… 
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