Several autosomal recessive causes of FGD have been identified, for example, mutations in the gene of the ACTH receptor, melanocortin-2 receptor (MC2R), caused FGD type 1, or in the melanocortin-2 receptor accessory protein (MRAP) are classified as FGD type 2 [10–12]. The gene discussed is MRAP; the disease is Aarskog-Scott syndrome, X-linked.