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Abstract Background The deafness-associated gene mutation profile varies greatly among regions and races. Due to the multi-ethnic coalition of over one thousand years, non-syndromic deafness (NSD) patients of Uyghur ethnicity may exhibit a unique deafness-associated gene mutation spectrum as compared to Han Chinese deaf population. Methods In order to characterize nine loci of four deafness-associated genes of Uyghur NSD patients in comparison with Chinese Han deaf population, NSD patients (n = 350) were enrolled, including Uyghur (n = 199) and Han Chinese (n = 151). Following the history taking, blood samples were collected for DNA extraction. DNA microarray was performed on nine loci of four deafness-associated genes, including 35delG, 176-191del16, 235delC, 299-300delAT, 538C > T, 1555A > G, 1494C > T, 2168A > G, and IVS7-2A > G. The samples that showed the absence of both wild and mutant probe signals were tested for further DNA sequencing analysis. Results The mutations in the nine loci of prevalent deafness-associated genes were detected in 13.06% of Uyghur NSD patients and 32.45% of Han Chinese patients (P < 0.05), respectively. GJB2 mutation was detected in 9.05% of Uyghur patients and 16.56% of Han Chinese patients (P > 0.05), respectively. 235delC was the hotspot mutation region in NSD patients of the two ethnicities, whereas 35delG was the mutation hotspot in Uyghur patients. 187delG mutation was detected for the first time in Uyghur NSD patients and considered as an unreported pathological variant of GJB2. SLC26A4 mutation was found in 2.01% of Uyghur patients and 14.57% of Han Chinese patients (P < 0.05), respectively. The frequencies of mtDNA 12S rRNA mutation in Uyghur and Han Chinese patients were 2.01% and 2.65% (P > 0.05), respectively. The NSD patients exhibited a low frequency of GJB3 mutation regardless of ethnicity. Conclusion Prevalent deafness-associated gene mutations in the nine loci studied were less frequently detected in Uyghur NSD patients than in Han Chinese patients. GJB2 was the most common mutant gene in the two ethnicities, whilst the two ethnicities differed substantially in hotspot mutations. A low-frequency SLC26A4 mutation was detected in Uyghur NSD patients. Uyghur NSD patients differed significantly from Han Chinese patients in gene mutation profile.

Reduction in DNA repair capacity is associated with increased rates of birth defects, cancer, and accelerated aging. According to some earlier studies, genetic polymorphisms in DNA repair genes might influence the repair activities of the enzymes predisposing individuals to cancer risk. Owing to the presence of these genetic variants, inter-individual and ethnic differences in DNA repair capacity have been observed in various populations. Polymorphisms in DNA repair genes and differences in repair capacity between individuals have been widely reported in different cancers. We conducted a case-control study to examine the role of genetic polymorphisms in XRCC1 Gln632Gln (rs3547), Arg399Gln (rs25487), Arg280His (rs25489), Arg194Trp (rs1799782) in the risk of laryngeal cancer in different ethnic groups in Xinjiang. This study included 58 laryngeal cancer patients and 120 healthy controls age- and sex-matched without cancer. The genotypes of XRCC1Gln632Gln (rs3547), Arg399Gln (rs25487), Arg280His (rs25489) and Arg194Trp (rs1799782) were analyzed by PCR-RFLP, and the odds ratio (OR) and 95% confidence interval (CI) were calculated using an unconditional logistic regression model. C/T (hybrid) and T/T (mutant) genotypes of XRCC1 Arg280His (rs25489) revealed no statistical significance in the risk of laryngeal cancer (P>0.05), whereas the genotypes of XRCC1 Gln632Gln (rs3547), Arg399Gln (rs25487), Arg280His (rs25489), Arg194Trp (rs1799782) showed a higher risk than the controls (P<0.01) in Han, Uygur, and Kazak nations. In conclusion, the current study suggests that XRCC1 Gln632Gln (rs3547), Arg399Gln (rs25487), and Arg194Trp (rs1799782) polymorphisms may be associated with laryngeal cancer risk in the Han, Uygur, and Kazakh populations in Xinjiang. Individuals carrying genotype Arg/Gln+Gln/Gln showed a greater risk than those carrying Arg/Arg for laryngeal cancer in the Han, Uygur and Kazakh ethnic groups, and the odds ratios are 1.47, 1.32, and 0.77., Competing Interests: None., (IJCEP Copyright © 2018.)

We aim to identify the mutations of deafness genes using massively parallel DNA sequencing in the 12 Uyghur families. SNPscan method was used to screen against the 124 sites in the common deafness genes in probands. Subjects with SNPscan negativity were subject to massively parallel DNA sequencing for the sequencing of 97 genes known to be responsible for hearing loss. Eight families (66.7%) showed biallelic mutations in probands, including MYO15A mutation ( 6892C>T in J02 family, 9514C>T/7894G>T in J07 family, and 9514C>T in J16 family), MYO7A mutation ( 1258A>T in J03 family), TMC1 mutation ( 773G>A in J09 family and 1247T>G/1312G>A in J11 family), and PCDH15 mutation ( 4658delT in J08 and J13 families). Six novel types of mutation were identified including 6892C>T , 9514C>T/7894G>T , and 9514C>T in MYO15A gene, 1258A>T in MYO7A , 773G>A in TMC1 , and 4658delT in PCDH15 . The ratio of nonsense mutation and frameshift mutation was comparatively high. All these indicated that the mutation types reported in this study were rare. In conclusion, rare deafness genes were identified in the Uyghur families using massively parallel DNA sequencing, part of which were suggested to be related to the pathogenesis of the disease.

Objective: To investigate the frequency of the mutations in Uyghur nonsyndromic deafness groups in Kashgar region of Xinjiang province by means of screening the common mutations of known deafness genes in China., Methods: One hundred and seventy-four Uyghur patients with hearing loss were involved in this study. Questionnaire survey was conducted and peripheral blood samples were collected for polymerase chain reaction. Screening was performed for 35delG, 176-191del16, 235delC, 299-300delAT, 1555A > G, 1494C > T, 2168A > G and IVS7-2A > G. DNA sequence analysis was performed for the samples with absent signals at some loci. SPSS 17.0 software was used to analyze the data., Results: Mutation of GJB2 was the most common among the three known deafness genes. 187delG was found for the first time in Uyghur groups with hearing loss and was a new pathological mutation of GJB2. The mutation rate of SLC26A4 was low in the experimental group with no significant difference when compared with the control group. The mtDNA 12S rRNA mutation rate in the deaf group was low but not detected in the control group. In addition, mutations were not detected in 17 cases among the 20 patients with positive family history., Conclusion: The mutation rate and dominant mutation of Uyghur ethnic nonsyndromic deaf groups have their own characteristics, it is necessary to conduct a sequence analysis and a stemma studying for an aim of perfecting the mutation spectrum of Uyghur deafness gene.