All STAT1-KO animals of 12–13 weeks presented hearing impairment suggesting a 100% incidence, while STAT1-KO mice of 9 and 18 weeks showed hearing impairment in 3 out of 8 and 7 out 13, respectively, suggesting a moderate incidence ranging from 37.5–54%. The gene discussed is STAT1; the disease is Hearing impairment.