[Mutation of GJB2 gene in nonsyndromic hearing impairment patients: analysis of 1190 cases].
OBJECTIVE
To analyze the sequence of GJB2 gene in nonsyndromic hearing impairment (NSHI) patients in China.


METHODS
Peripheral blood samples were obtained from 1190 NSHI patients randomly selected from the Deaf and Mute Schools of Beijing, Hebei, Heilongjiang, Jilin, Inner Mongolia, Shanxi, Henan, Hubei, Shaanxi, Gansu, Ningxia, Qinghai, Anhui, Jiangsu, Shanghai, Fujian, Guangdong, and Guangxi, and 301 children with normal hearing level used as controls. Genomic DNA was extracted by extraction kits to undergo polymerase chain reaction and sequencing so as to detect the mutations of GJB2 gene.


RESULTS
Sixteen pathogenic mutations of GJB2 gene were found, the most common of which included 235delC, 299-300delAT, and 176del16bp. 250 patients (21.05%) carried definite GJB2 mutations, 245 of which (98%) carried at least one of these 3 common mutations. 222 of the 250 patients (88.80%) carried the mutation 235delC with a detection rate of 18.66%. 62 of the 250 patients (24.80%) carried the mutation 299-300delAT with a detection rate of 5.21%. 19 of the 250 patients (7.60%) carried the mutation 176del16bp with a detection rate of 1.60%. The detection rates of these 3 mutations in the NSHI patients were all significantly higher than those among the controls (all P<0.01).


CONCLUSIONS
The hot spot of GJB2 gene mutations in Chinese NSHI patients is 235delC, followed by 299-300delAT and 176del16bp. These results establish a fundamental basis for drawing a spectrum of GJB2 gene mutation among Chinese population.
Yu
Fei
F
Department of Otolaryngology, Head and Neck Surgery, Institute of Otorhinolaryngology, Genetic Testing Center for Deafness, People's Liberation Army General Hospital, Beijing 100853, China.
Han
Dong-yi
DY
Dai
Pu
P
Kang
Dong-yang
DY
Zhang
Xin
X
Liu
Xin
X
Zhu
Qing-wen
QW
Yuan
Yong-yi
YY
Sun
Qing
Q
Xue
Dan-dan
DD
Li
Mei
M
Liu
Jun
J
Yuan
Hui-jun
HJ
Yang
Wei-yan
WY
D000293:Adolescent; D000328:Adult; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D002681:China; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D004252:DNA Mutational Analysis; D005787:Gene Frequency; D034381:Hearing Loss / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D009154:Mutation
D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26