RYR1 and skeletal muscle disorder: Given that MH and CCD are autosomal dominantly inherited skeletal muscle disorders and that ablation of one Ryr1 allele is well-tolerated in mice [14], [15], we hypothesized that preferential ASGS of the mutant RyR1 allele in YS/+ and IT/+ knock-in mice would correct RyR1 function in these mice.