Carrier frequency of GJB2 (connexin-26) mutations causing inherited deafness in the Korean population.
Mutations in the GJB2 gene are associated with hereditary hearing loss. Although most studies of GJB2 mutations have dealt with hearing-impaired patients, there are few reports of the frequency of these mutations in the general population. The purpose of this study is to evaluate the prevalence of GJB2 mutations causing inherited deafness in the general Korean population. Blood samples were obtained from 2,072 newborns with normal hearing. The dried blood samples were subjected to PCR to amplify the entire coding region of the GJB2 gene, which was followed by direct DNA sequencing. A total of 24 different sequence variants were identified in the coding region of GJB2, including eight pathogenic mutations (p.V37I, p.G45E, p.R143 W, c.176_191del16, c.235delC, c.292_298dup7, c.299_300delAT and c.605ins46), four polymorphisms (p.V27I, p.E114G, p.G160S and p.I203T), six unclassified variants (p.G4D, p.S85Y, p.T123 N, p.R127H, p.A171T and p.F191L) and six novel variants (p.W3T, p.I20L, p.K41E, c.147C > T, c.186C > T and c.576A > G). Pathogenic mutations causing inherited deafness were identified in 3% (62/2,072) of the newborns with normal hearing. Of the eight pathogenic mutations found, p.V37I was the most common (1.35%, 28/2,072), followed by c.235delC (1.25%, 26/2,072). These data provide information about carrier frequency for GJB2-based hearing loss and have important implications for genetic diagnostic testing for inherited deafness in the Korean population.
Han
Sung-Hee
SH
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea.
Park
Hong-Joon
HJ
Department of Otorhinolaryngology, Soree Ear Clinic, 46-16, Chungdam-dong, Kangnam-gu, Seoul, South Korea.
Kang
Eun-Joo
EJ
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea.
Ryu
Jae-Song
JS
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea.
Lee
Anna
A
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea.
Yang
Young-Ho
YH
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea.
Lee
Kyoung-Ryul
KR
Division of Molecular Genetics, Department of Laboratory Medicine, Seoul Clinical Laboratories, Seoul Medical Science Institute, 7-14, Dongbingo-dong, Yongsan-gu, Seoul, South Korea. dkrlee@scllab.co.kr.
D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004252:DNA Mutational Analysis; D003638:Deafness / Q000175:diagnosis / Q000235:genetics*; D006580:Genetic Carrier Screening; D020022:Genetic Predisposition to Disease; D006801:Humans; D007231:Infant, Newborn; D009154:Mutation / Q000235:genetics*; D015997:Neonatal Screening
D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26