Screeing Using SNPscan Method for GJB2 Gene Mutation among Non-syndromic Deaf Patients of the Dominant Ethnic Minorities in Xinjiang / 听力学及言语疾病杂志

Objective To investigate the prevalence and characteristics of GJB2 mutations in Uygur,Hui, Kazak and Kirgiz ethnic patients with non-syndromic hearing loss(NSHL)from the Xinjiang Uygur Autonomous Region of China.Methods With the permission,we collected 565 patients with moderately severe to profound sen-sorineural hearing loss,including Uygur,Hui,Kazak and Kirgiz ethnic minorities from 14 cities of Xinjiang.Pe-ripheral blood samples were obtained to extract genomic DNA.The SNP classification technology was for common pathogenic GJB2 gene mutations.ResuIts The pathogenic allele frequency of GJB2 gene were 10.16%(87/856 ), 15.85%(13/82),10.16%(13/128),1.56%(1/64)in the NSHL patients of Uygur,Hui,Kazak and Kirgiz minori-ties,respectively.And these differences were statistically significant (χ2 =8.140,P=0.043).c.235delc was only found in the Uygur and Hui with the allele frequency of 5.14 %(44/856)and 13.41 %(11/82),respectively.And c.35delG was found in Uyhur,Hui,Kazak and Kirgiz with allele frequencies were 3.15% (27/856),1.21% (1/82),8.59%(11/128)and 1.56% (1/64),respectively.ConcIusion GJB2 gene mutations had a higher incidence in Xinjiang NSHL patients,GJB2 gene mutation spectrum had differences in Uygur,Hui,Kazak and Kirgiz,c. 235delC the hotspot mutation region in Uygur and Hui nationalities NSHL patients,while c.35delG is the hotspot mutation region in NSHL patients of Uygur,Kazak and Kirgiz ethnicities.

Prevalence Study of GJB2,SLC26A4 and mtDNA 12S rRNA1555A>G Mutations in Hui Ethnic Group Patients with Non-Syndromic Hearing Loss from Northwest China / 听力学及言语疾病杂志

Objective To investigate the prevalence of GJB2 ,SLC26A4 and mitochondrial DNA 12S rRNA m .1555A>G(mtDNA 1555A>G) mutations in Hui ethic group patients with nonsyndromic hearing loss (NSHL) from Northwest China .Methods A total of 420 peripheral blood samples were collected from unrelated Hui ethic group probands with NSHL in Northwest China .Amplified the target gene by polymerase chain reaction (PCR) af-ter extracting genomic DNA from whole blood .The mtDNA 1555A>G mutation was detected by PCR -Alw26I di-gestion ,then direct sequencing was used to the positive samples of mtDNA 1555A> G ,the coding region of GJB2 gene ,exon 8 and 19 of SLC26A4 gene .Results There were 11(2 .62% ) cases caused by mtDNA 1555A>G homo-zygous mutation in 420 patients with NSHL .There were 41(9 .76% ) cases including homozygote and compound het-erozygote ,caused by GJB2 gene mutation ,which was the most frequent deafness -related gene .The allel frequency of c .235delC accounted for 6 .90% ,as well as the most frequent(51 .33% ) mutational pattern in GJB2 gene .There were 20 patients(4 .76% ) were found carring two allel mutations in SLC26A4 gene .The allel frequency of c .919 -2A>G was 5 .0% ,accounting for a total of 68 .85% in all base alterations of SLC26A4 gene ,which was the major mutant form of SLC26A4 gene .Conclusion GJB2 gene is the most common deafness -gene in Hui ethnic group pa-tients with NSHL from Northwest China ,while c .235delC is the main mutant form ,and c .919-2A>G is the hot-spot mutation of SLC26A4 gene .Through this study we can provide the molecular epidemiology basis for Hui ethnic group patients with NSHL from Northwest China in genetic diagnosis ,genetic counseling and therapy by associated testing of three frequent hearing loss genes .

Molecular analysis of mitochondrial DNA A1555G and connexin 26 gene(GJB2) in Chinese Northwest population with nonsyndromic sensorineural hearing loss / 中国耳鼻咽喉头颈外科

OBJECTIVE To investigate the incidence of the mitochondrial DNA 12SrRNA A1555G and connexin 26 gene (GJB2) in Chinese northwest population with nonsyndromic sensorineural hearing loss,and to explore the relationship between mitochondrial DNA A1555G and mutation of GJB2 gene. METHODS Blood samples were obtained from 221 patients with nonsyndromic sensorineural hearing loss in Northwest of China; Genomic DNA was extracted from the isolated leukocytes ; Screening the mitochondrial A1555G mutation by PCR-Alw26l digestion and sequence analysis, PCR and direct sequencing were used to analyze the coding region of GJB2 gene. RESULTS The homoplasmic A1555G mutation was found in 21 individuals of 221 patients,17 of these 21 patients had been treated with aminoglycosides. Eleven different variants of GJB2 were found in all patients ,the disease-causing mutations of GJB2 were 44 individuals in these patients(44/221), The mutation 235delC is found in 54.54 % of all disease-causing mutations ; Among 21 patients with the A1555G mutation, 11 cases were found polymorphic change in GJB2 gene ,only 1 case had V37I heterozygous mutations ,other 9 cases were not found any nucleotide changes of GJB2 gene. CONCLUSION The mtDNA 12SrRNA A1555G mutation has a high incidence in Chinese northwest population with non-syndromic sensorineural hearing loss.The 235delC mutation in the GJB2 gene is most frequent mutations responsible for non-syndromic hearing impairment in this region .It is unlikely that the GJB2 gene is a major modulatory factor for hearing loss due to the A1555G mutation in Chinese population.

Study on nuchal skin thickness of normal fetal by ultrasonography / 中华超声影像学杂志

ObjectiveTo explore ultrasonographic featurs of nuchal skin of normal fetus in its thickness and changes.MethodsThe thickness of nuchal skin of 900 normal fetal was measured by abdominal ultrasound with 7.5 MHz probe.ResultsThe nuchal skin only displayed whole layer before pregnant 27 weeks. After pregnant 27 weeks, the derma and subderma layer was distinguishable, the whole thickness of nuchal skin was ( 1.18 ? 0.05 )mm (10 weeks) to ( 6.01 ? 0.46 )mm (40 weeks) in normal fetus. All layers of nuchal skin were increased proportionally with gestation [r= 0.973 (whole layer), P 0.05 ).Conclusions The abnomal chromosome of fetus could be sifted by the thickness of nuchal skin and the character of sonographic image. It′s a useful diagnostic method for eugenics.

Molecular epidemiological study of GJB2 mutations in the prelingual deafness in northwestern China / 解放军医学杂志

Objective To investigate the molecular epidemiology of GJB2 mutations as a causative effect of prelingual deafness in northwestern China. Methods The medical history of 274 deaf-mute students was collected. Blood samples were obtained from them with informed consent. GJB2 gene sequences of genomic DNAs were amplified by polymerase chain reaction (PCR) with a pair of primers, and bidirectional sequencing of PCR products was performed and analyzed with DNAStar Software. Results A total number of 274 deaf-mute students were diagnosed as non-syndromic hearing impairment, and profound prelingual deafness. Two kinds of polymorphism, seven pathologic mutations and one novel mutation were revealed in the GJB2 screenings of them, and 79G→A and 341A→G were polymorphism with high frequency. Conclusion GJB2 gene mutation is the causative gene in the prelingual deafness with a high incidence of 10.95% in northwestern China. Based on the investigation, it is clear that screening of GJB2 gene mutation should play a significant role in early diagnosis of deaf-mutism in this region.