Phenotypic characteristics of familial glucocorticoid deficiency (FGD) type 1 and 2

Summary Context Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disorder as a result of mutation in genes encoding either the ACTH receptor [melanocortin 2 receptor (MC2R)] or its accessory protein [melanocortin 2 receptor accessory protein (MRAP)]. The disorder is known as FGD type 1 and 2, respectively. Objective The aim of the study was to compare the phenotype/genotype relationships between FGD 1 and 2. Design and patients Forty patients with missense MC2R mutations and 22 patients with MRAP mutations were included. Forty‐four of these patients had been referred for genetic screening and 18 were patients published by other authors. Results The median age at presentation for FGD type 1 was variable at 2·0 years; range 0·02–16 years, and this was associated with unusually tall stature, mean height SDS + 1·75 ± 1·53 (mean ± SD). In contrast, FGD type 2 presented at a much earlier median age (0·08 years; range at birth to 1·6 years) (P