Cavalier King Charles Spaniels Muscular Dystrophy (CKCS-MD)
Cavalier King Charles Spaniels Muscular Dystrophy (CKCS-MD) is an X-linked recessive disorder in which the loss of dystrophin causes progressive muscle weakness, respiratory insufficiency, and cardiomyopathy. Since males have only one X chromosome, they are more susceptible to inheriting Cavalier King Charles Spaniels Muscular Dystrophy because they need only one parent to pass the gene to them. For females to inherit the gene, both parents must carry it. Females are more often only carriers of the gene. Dystrophin, a cytoskeletal protein located between the extracellular matrix and inner cytoskeleton of muscle fibers. It stiffens muscle fibers, acting as a type of shock absorber by providing resistance against deformation. A deficiency of dystrophin leaves the fibers susceptible to contraction induced microfissures, which disrupt calcium homeostasis, ultimately resulting in cellular necrosis. Affected dogs suffer from raised serum creatine kinase levels, muscle atrophy with contractures, hyaline myofiber degeneration with mineralization, endomysial and perimysial fibrosis with fatty infiltration, and cardiomyopathy
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