MC2R and achalasia-alacrima syndrome: Thus, although it is known that approximately 10–15% of individuals who have ACTH resistance as part of the Triple A (Allgrove) syndrome (AAAS, ALADIN) (OMIM: 231550) do have evidence of mineralocorticoid deficiency,26 disturbances in renin-sodium homeostasis in patients with other ACTH-resistance syndromes (FGD1 due to MC2R mutations; FGD2 due to mutations in MRAP [607398]) are not well established.27