How can someone’s gender differ from the sex they were assigned at birth?
What neuroscience can tell us about gender identity and what the DSM actually says (November 2026) I wrote this in response to people who say or imply that being trans is a sign of mental illness. At birth, sex is usually assigned based on visible anatomy. Gender identity is our inner sense of our gender. Research suggests that genes and exposure to hormones before birth may help shape that sense of self. Studies have also found differences in brain structure and function, though researchers are still working out what those findings mean. These findings offer clues to why someone’s gender identity can differ from the sex they were assigned at birth. How those influences come together for any one person is still an open question. And how our sense of gender develops is a different question from when we recognize it or find words for it. For some of us, that takes decades. The DSM-5-TR answers a different question. It defines gender dysphoria as a diagnosis that requires clinically signi...