Among 108 cases with a 2 copy loss of the whole CKMT1B-STRC-CATSPER2 gene region, 52 cases were male and the prevalence of DIS in patients with hearing loss associated with a 2 copy number loss of the STRC gene was estimated to be 37.1% (52/140). The gene discussed is CKMT1B; the disease is hearing loss disorder.