GJB2 and hearing loss disorder: According to a nationwide genetic study about the GJB2 mutation spectrum in China, there was a significant difference in the detection rate of pathogenic GJB2 allele depending on the region within China, varying from 4% in Guangxi to 30.4% in Jiangsu, while the overall frequency of pathogenic GJB2 allele among moderate to severe hearing loss was 17.9%26.