GMPPB and muscular dystrophy-dystroglycanopathy, type A: It is associated with Walker-Warburg syndrome, a heterogeneous group of muscular dystrophy-dystroglycanopathy (MDDG) conditions that can be caused by homozygous mutations in the genes FKTN (Fukuyama syndrome), POMT2 and POMGnT1 (muscle-eye-brain disease), as well as POMGNT2, FKRP, LARGE, ISPD, GTDC2, TMEM5, B3GALNT2, SGK196, B3GNT1, and GMPPB [98–101].