SH2D1A and hyperinsulinemic hypoglycemia, familial, 4: Initially reported in 2006 in a cohort of patients with a clinical phenotype close to that of SH2D1A-deficient patients (XLP-1), XIAP deficiency was further denominated XLP-2, since XIAP is located in the immediate vicinity of SH2D1A on the X chromosome (57).