RYR1 and congenital myopathy with cores: The last two decades have seen an ever-increasing expansion of the RYR1-associated phenotypic spectrum: in addition to dominantly inherited CCD, other (mainly recessively inherited) congenital myopathies named after the predominant finding on muscle biopsy—Multi-minicore Disease (MmD) [2], Centronuclear Myopathy (CNM) [3], and Congenital Fibre Type Disproportion (CFTD)—have been described [4].