FKRP and muscular dystrophy-dystroglycanopathy type B5: Mutations in fukutin-related protein (FKRP), which encompass a heterogeneous spectrum of dystroglycanopathies, ranging from limb-girdle MD type 2I (LGMD2I, also known as LGMDR9) to several forms of congenital MD (MDC1C) [8,9,10], are also characterized by respiratory impairment due to loss of diaphragm function.