Transsexualism in Female Monozygotic Twins: A Case Report

Abstract

Objective: A case report is presented of a gender identity disorder involving a pair of female monozygotic twins who requested sex reassignment. As far as we know, this case is the first in psychiatric literature and supports a genetic aetiology of this disorder. Clinical picture: The patients were two 18-year-old female monozygotic twins who had showed symptoms of transsexualism since early childhood. They had no other physical or psychiatric disorder except borderline mental functioning. Treatment: The patients were referred for sex reassignment. Outcome: They were lost to follow up after initial evaluation. Conclusion: In addition to other possible (yet not confirmed) causes of trans-sexualism, a genetic basis for this disorder is suggested by this case.