KCNJ8 and Cowden syndrome 1: This is the first report showing a direct genotype-phenotype correlation in CS skeletal muscle, revealing how Kir6.1wt/VM mutation in the KATP channel Kir6.1 subunit is associated with a reduction of limb strength, skeletal muscle atrophy, autophagy, and connective tissue replacement of myofibers in this animal model of CS.