In this article, I argue that the medical conceptualization of gender identity in the United States has entered a “new regime of truth.” Drawing from a mixed-methods analysis of medical journals, I illuminate a shift in the locus of gender identity from external genitalia and pathologization of families to genes and brain structure and individualized self-conception. The sexed body itself has also undergone a transformation: Sex no longer resides solely in genitalia but has traveled to more visible parts of the body, implicating racialized aesthetic ideals in its new formulation. The re-imagining of gender identity as genetically and neurologically inscribed and the expanding locus of sex correspond to an inversion of the relationship between gender identity and the sexed body as well as shifts in medical jurisdiction. Whereas psychiatrists in the 1960s, ’70s, and ’80s understood gender as stemming from genital sex, the less popular idea that gender identity precedes the sexed body has gained traction in recent decades. If gender identity once derived from the sexed body, the sexed body must now be brought into alignment with gender identity. The increasing legitimacy of self-defined gender identity, the expanding definition of racialized sex, and the inversion of the sex–gender identity relationship elevates the role of surgeons in producing racialized and sexed bodies.