The Biological Contributions to Gender Identity and Gender Diversity: Bringing Data to the Table
The American Psychological Association defines gender identity as, “A person’s deeply-felt, inherent sense of being a boy, a man, or a male; a girl, a woman, or a female; or an alternative gender (e.g., genderqueer, gender nonconforming, gender neutral) that may or may not correspond to a person’s sex assigned at birth or to a person’s primary or secondary sex characteristics” (American Psychological Association, Am Psychol 70(9):832–864, 2015). Here we review the evidence that gender identity and related socially defined gender constructs are influenced in part by innate factors including genes. Based on the data reviewed, we hypothesize that gender identity is a multifactorial complex trait with a heritable polygenic component. We argue that increasing the awareness of the biological diversity underlying gender identity development is relevant to all domains of social, medical, and neuroscience research and foundational for reducing health disparities and promoting human-rights protections for gender minorities.
KeywordsGender identity Transgender Gender dysphoria Heritability Genetics Twin studies
We acknowledge the many transgender and gender non-conforming children and adults who have participated in the research cited in this paper. We express great gratitude to the youth and adults who participated in our Community Engagement Studios and who shared their thoughts on the importance and value of genomics research on gender identity and voiced their concerns about potential misuse of the results.
Compliance with ethical standards
Conflict of interest
All authors declare that they have no conflicts of interest.
Human and Animal Rights
This article does not contain any studies with human participants or animals performed by any of the authors.
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