A four-generation pedigree affected with X-linked adrenal hypoplasia congenita due to a novel missense DAX1 mutation

Abstract

To report on the clinical pictures of 7 patients from a pedigree affected with X-linked adrenal hypoplasia congenita (XL-AHC) and hypogonadotropic hypogonadism (HH) and the underlying mutations. Seven patients were identified from a four-generation pedigree affected with XL-AHC and HH. Their clinical features, endocrinological changes, treatment and drug response were recorded. The patients were subjected to next-generation sequencing, and the result was verified by Sanger sequencing. PolyPhen-2 was used for predicting the influence of the mutation on protein production. Three deceased patients had manifested adrenal insufficiency (AI) within one year after birth. Two died at 6 and one died at 12. The four survivors presented with salient clinical and endocrinological features of AHC and HH, adrenal and testicular atrophy, and renin-angiotensin compensation. Two adult patients had testicular micro-stone detected by ultrasound.One of them also had remarkable seminiferous tubule degeneration by biopsy. The patients were followed up for 0.5 to 10 years. All required hyper-physiological dose of hydrocortisone to stabilize their clinical condition. In three patients, gonadotropic or androgen replacement induced cardinal masculine development but with unsatisfactory testis growth and sperm production.Genetic analysis revealed a novel missense c.827A>C (p.Q276P) mutation in a hotspot region within a highly conserved domain. PolyPhen-2 predicted the mutation to be highly hazardous. The novel p.Q276P mutation of the DAX1 gene probably underlies the XL-AHC and HH in this pedigree with variable clinical presentations in the patients.