RBCK1 and polyglucosan body myopathy 1 with or without immunodeficiency: This congenital disorder, also referred to as polyglucosan body myopathy-1 (PGBM1) [OMIM:610924], is an AR GSD caused by mutations on the RANBP-type and C3HC4-type zinc finger-containing 1 (RBCK1) gene located on chromosome 20p13 [206,207].