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. 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. The study highlights the genetic concordance in gender dysphoria, suggesting heritable mechanisms, while acknowledging the role of environmental and epigenetic factors. The twins' consistent gender identity development supports the strong association between genetic susceptibility and gender identity.