DYSF and neuromuscular disease caused by qualitative or quantitative defects of dysferlin: Nonetheless, these results rule out any direct effects of dysferlin deficiency on myofilament force production and indicate that altered contractile function of BLAJ muscles is not due to intrinsic differences in myofilament responses to Ca2+, and rather support the likely involvement of altered levels of key proteins associated with EC coupling and Ca2+ handling in dysferlinopathy-related contractile dysfunction.