It is an autosomal recessive disorder resulting from ACTH resistance, typically presenting between the neonatal period and late childhood; with hyperpigmentation, hypoglycaemia and seizure.1–4 The first inactivating melanocortin 2 receptor (MC2R) mutations in FGD were described in 1993.5,6 Since then, multiple mutations have been identified throughout the receptor, the majority of which are homozygous or compound heterozygous missense mutations; FGD resulting from MC2R mutations accounts for ∼25% of all FGD and is now known as FGD type 1 (OMIM#202200). This evidence concerns the gene MC2R and Aarskog-Scott syndrome, X-linked.