The rare form of congenital adrenal hyperplasia caused by an autosomal dominant form of STAR deficiency

The steroidogenic acute regulatory protein (StAR) is crucial for transport of cholesterol to mitochondria where biosynthesis of steroids is initiated. Loss of StAR function due to autosomal-recessive mutations in the STAR gene leads to lipoid congenital adrenal hyperplasia (LCAH) which is characterized by impaired synthesis of adrenal and gonadal steroids, which causes adrenal insufficiency, primary ovarian failure in 46XX patients, or 46XY disorder of sex development (DSD). However, there were a few reports of 46 XY DSD patients with LCAH caused by a heterozygous mutation in the STAR gene. Here, we describe another rare case of LCAH in a 46XY patient with DSD and primary adrenal insufficiency due to an autosomal-dominant mutation in the STAR gene.