Central core disease
At a minimum, these SNPs are known to be related, and others may also be
Central core disease (CCD) is a congenital myopathy in which type I skeletal muscle fibers exhibit amorphous areas ("cores") that lack mitochondria and oxidative enzyme activity that run the length of the myofiber. It is a rare disorder that exhibits both autosomal dominant and recessive modes of inheritance. Patients have variable clinical features ranging from asymptomatic to exhibiting severe muscle weakness. However, up to 40% of patients exhibiting cores might be clinically normal. Common clinical symptoms include muscle atrophy, lower limb skeletal weakness, floppy infant syndrome, and skeletal deformities, e.g., hip displacement and scoliosis.[PMID 16917943]
Two related diseases, multiminicore disease (MmD) and nemaline myopathy have been identified and may be distinguished from CCD based on histological examination of muscle specimens and by certain clinical features in some cases. However, all these conditions demonstrate clinical and genetic heterogeneity and show some degree of overlap.