Deficiency of CHKB (autosomal recessive mutations in CHKB) was first described in a natural occurring mouse model showing a muscular dystrophy with a unique mitochondrial morphology in muscle fibres.18 Subsequently, the same phenotype was reported in humans.19 Single‐nucleotide polymorphisms in the CHKB locus have been associated with susceptibility to narcolepsy with cataplexy.20 No human phenotype has been associated to defective CHKA to date. The gene discussed is CHKB; the disease is muscular dystrophy.