Interestingly, in our study plasma CK concentrations did not correlate with muscle damage in dysferlin-null mice; a phenomenon that has been noted in late stage disease in both mdx [51] and DMD patients [reviewed in [52]], where CK levels can vary dramatically over time, and with the loss of viable myofiber area [51–53]. The gene discussed is DYSF; the disease is Duchenne muscular dystrophy.