PAX7 and muscular dystrophy: To investigate the potential that modulation of myostatin in muscular dystrophy might lead to exhaustion of the satellite cell pool, we quantified Pax7-positive nuclei in two dystrophic dogs, including one GRippet (Tabitha) and another Mstn+/+ GRMD dog (Hagatha), as well as two GRMD carriers that differed on myostatin status (Endora (Mstn+/+) and Esmerelda (Mstn+/−)).