Abstract
Abnormalities in the DAX-1 gene (dosage-sensitive sex reversal-adrenal hypoplasia. gene on the X chromosome) are a well-recognized cause of congenital adrenal hypoplasia. DAX-1 is expressed in the adrenal cortex, gonads, hypothalamus and anterior pituitary, which gives rise to the clinical features of this deletion. Presentations are varied but salt-wasting and/or hypoglycaemia are the most common in an infant, with late onset of hypogonaclotrophic hypogonadism. Over 80 different mutations in this gene have been identified. We present three unrelated cases with variable clinical presentations, all with novel mutations in the DAX-1 gene.