Complex glycerol kinase deficiency is a contiguous gene syndrome caused by partial deletion of the Xp21 chromosome, which contains genes responsible for deficiency of the enzyme glycerol kinase (GKD, OMIM 307030), Duchenne muscular dystrophy (DMD, OMIM 310200), congenital adrenal hypoplasia (AHC, OMIM 300200), and intellectual disability (deletion in IL1RAPL1 gene) [6,7,8]. Here, GK is linked to hyperinsulinemic hypoglycemia, familial, 4.