Clinical Findings in Two patients with DSD 46XY caused by new variant of the <i>Desert Hedgehog</i> Gene and review of the literature of the role of DHH signaling pathway in sex development

Abstract

Mutations in the gene DHH are an extremely rare cause of disorders of sex development 46,XY (DSD,46XY). The article describes the clinical cases of two unrelated patients with gonadal dysgenesis 46,XY with female phenotype. By using a next generation sequencing method, in both cases the same biallelic variant substitution c. 419T>G in the DHH gene was revealed. Taking into account the data on the role of DHH in the formation of the nervous system, the diagnosis of minifascicular polyneuropathy at the preclinical stage was confirmed in both cases. These cases demonstrate the value of using NGS, which allows simultaneous analysis of a wide range of candidate genes in DSD and the diagnosis of comorbidities before the development of the clinical picture. These are the first descriptions of patients with mutations in the DHH gene in the Russian population.