P-055 Monozygotic Transgender Male Twins: A Case Report Highlighting Genetic Concordance in Gender Dysphoria

This case report presents monozygotic transgender male twins, assigned female at birth, who were referred to an endocrinology clinic for hormonal management of gender dysphoria. Both twins, aged 27, have undergone mastectomy and are on testosterone therapy, showing physical changes such as increased body hair and voice deepening without mood-related side effects. Their case highlights the genetic concordance in gender dysphoria, as twin studies suggest a strong heritable component in gender identity development, although environmental and epigenetic factors also contribute.