ESPE Abstracts

In the past year, basic and genetic studies revealed again novel genes and mechanisms implicated in 46,XX and 46,XY DSD. The Fgf9^-/- mouse model of human synostosis syndromes revealed an unexpected male-to-female sex reversal phenotype, so far not observed in humans. Specific heterozygous human WT1 gene variants located in the 4^th zinc finger were found to cause 46,XX virilization due to (ovo-)testicular DSD, and the transcription factor FKBP4 was reported as novel candidate gene for androgen insensitivity syndrome. Furthermore, several 46,XY patients suffering from complex syndromes owing to congenital disorders of glycosylation were recognized with a DSD phenotype likely due to early disruption of sexual development. Single-cell sequencing has been introduced as a promising method to elucidate the complex mechanisms of gonadal and sexual developmental, and is predicted to help understanding the pathomechanisms of DSDs. Several clinical studies on patient reported outcomes have been published informing on topics such as sex assignment, needs in adolescents and during transition for sexual health as well as on long-term outcome after genital surgery. In transgender medicine, the largest body of literature was in topic (long-term) effects of hormonal treatments and their current controversies. Studies reported on possible behavioral and neurobiological effects of GnRH agonist treatment, and on increased risk of intracranial meningioma in trans women using high dose cyproterone acetate. In addition, studies addressed thrombosis risk and bone health related to GnRH agonist and gender affirming hormone therapy. However, many of these studies suffer from limitations including small numbers, retrospective and/or single center design, non-uniform study protocols and short observation period.