UCN2 and myopathy: In a previous report, we demonstrated that the passive transfer of IgG purified from anti-SRP+ or anti-HMGCR+ patients induces myopathy in mice, since the C-terminal domains of human and mouse HMGCR and SRP54 share 98% and 100% homology, respectively, allowing human aAbs to react against their cognate murine target [11].