Mutational analysis of candidate genes in a Chinese pedigree with dominantly inherited auditory neuropathy / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#Three genes including the OTOF, the DFNB59 and the DIAPH3 have been implicated previously in human non-syndromic auditory neuropathy. In this study, we aim to investigate whether DIAPH3 gene or the known deafness loci of 25 cloned autosomal dominant deafness (DFNA) genes contribute to the nonsyndromic hearing loss of a Chinese pedigree with dominantly inherited auditory neuropathy (AN).@*METHOD@#Nine members of the kernal pedigree in this family were selected. Genomic DNA was isolated from the peripheral leukocytes of the subjects using the Puregene DNA Isolation Kits. Firstly, the 5'UTR of DIAPH3 gene was PCR amplified in all subjects. Then, the DNA fragments spanning the entire coding regions of DIAPH3, GJB2 and GJB3 genes, and 50 exons in other 23 cloned DFNA genes were amplified using specific primers. Each fragment was purified and analyzed by direct sequencing. The resultant sequence data were compared with the standard sequence to identify deafness-associated mutations.@*RESULT@#PCR amplifications were successfully conducted. We failed to detect the presence either of c. --172G > A mutation in the 5'UTR that have been reported, or any other deafness-associated mutations in the whole DIAPH3 gene, by sequence analysis. We also did not find any known deafness-causing mutations among the 25 cloned DFNA genes.@*CONCLUSION@#The DIAPH3 gene, and the known deafness loci of 25 cloned DFNA genes seem not contribute to the pathogenesis of this Chinese AN family in this study, which suggesting new gene(s) involvement.

The application of improved CHQS for mass epidemiology study on hearing impairment / 临床耳鼻咽喉头颈外科杂志

Objective:To develop and evaluate the improved Chinese hearing questionnaire for school children(CHQS)for mass epidemiology study on hearing impairment in China.Method:Using the probability proportion to size(PPS) method, 8 412 residents were investigated in 40 clusters in Jiangsu province with the WHO ear diseases and hearing disorders survey protocol.87.9% of the residents aged 7 years and over answered the questionnaire and accepted the pure tone audiometry.Result:The prevalence of hearing impairment was 12.9% by the questionnaire. Compared with golden standard(pure tone audiometry), Sen=58.5%, Spe=96.7%, PV+=78.9%, PV-=91.7%, overall accuracy=90.0% . The sensitivity for women was higher than men.Conclusion:The questionnaire produced high efficiency and specificity values.It could be used in mass hearing screening, particularly in remote and rural area, although the sensitivity was as low as most questionnaires.

The application of improved CHQS for mass epidemiology study on hearing impairment / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To develop and evaluate the improved Chinese hearing questionnaire for school children (CHQS) for mass epidemiology study on hearing impairment in China.@*METHOD@#Using the probability proportion to size (PPS) method, 8412 residents were investigated in 40 clusters in Jiangsu province with the WHO ear diseases and hearing disorders survey protocol. 87.9% of the residents aged 7 years and over answered the questionnaire and accepted the pure tone audiometry.@*RESULT@#The prevalence of hearing impairment was 12.9% by the questionnaire. Compared with "golden standard" (pure tone audiometry), Sen = 58.5%, Spe = 96.7%, PV+ = 78.9%, PV- = 91.7%, overall accuracy = 90.0%. The sensitivity for women was higher than men.@*CONCLUSION@#The questionnaire produced high efficiency and specificity values. It could be used in mass hearing screening, particularly in remote and rural area, although the sensitivity was as low as most questionnaires.

Newborn hearing screening in the neonatal intensive care unit: a preliminary study / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To search for the prevalence and a screening model for hearing impairment in the neonatal intensive care unit (NICU) infants.@*METHOD@#Two-stage hearing screening program by automated auditory brainstem response (AABR) were used. A first test was performed as late as possible before discharge from the NICU. Those cases who failed the initial screening underwent a second test in an outpatient setting with an interval of one month. After a failure at the second screening, the infants were referred to our audiological center for further diagnostic evaluations within three months.@*RESULT@#The subjects included were 824 infants who discharged from NICU between September 2007 and August 2008. Seventy newborns (8.5%) failed the pre-discharge AABR test. Of those, fifty-five (78.6%) received the second AABR screening after one month, and nine referred again. These nine babies were evaluated with additional diagnostic audiological tests. Three of them were eventually identified to have sensorineural hearing loss, and one was diagnosed as auditory neuropathy. The total prevalence of hearing loss was 0.48%.@*CONCLUSION@#Two-stage screening program of AABR may be an ideal model for hearing screening in NICU infants. The prevalence of hearing loss in our group is lower than that reported in the literature.

Mutation analysis of mitochondrial 12S rRNA gene G709A in a maternally inherited pedigree with non-syndromic deafness / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship of mitochondrial DNA mutations with inherited deafness in a maternally inherited pedigree with non-syndromic deafness.</p><p><b>METHODS</b>The diagnosis was validated by hearing tests. Blood samples were collected from 18 maternal members of the family and 53 controls including 6 paternal members, 7 spouses and 40 unrelated individuals. DNA was extracted from the leukocytes in blood samples. The gene fragments of mitochondrial DNA 12S rRNA, tRNA(Ser(UCN)) and GJB2 gene were amplified by polymerase chain reaction(PCR). PCR products were analyzed by sequencing. Computerized 12S rRNA secondary structure modeling was carried out to characterize the mutation found in the family.</p><p><b>RESULTS</b>A novel mitochondrial DNA 12S rRNA 709 G to A transition was detected from all maternal members including 8 patients with hearing loss and other 10 symptom-free maternal members. Non-maternal members and other controls did not carry this mutation. In addition, the tRNA(Ser(UCN))A7445G, 12S rRNA A1555G and GJB2 gene mutations were not observed in the study. Computerized modeling showed that this mutation changed the eighth and ninth loop-stem structure of the 12S rRNA secondary structure.</p><p><b>CONCLUSION</b>In this family, 8 deaf patients carried the mitochondrial DNA 12S rRNA 709 G to A mutation, which is highly conservative in healthy adults. It was confirmed that the mitochondrial DNA 12S rRNA gene G709A was associated with non-syndromic inherited hearing loss. The other 10 maternal members carried the mutation, but they did not suffer from deafness, which might suggest that the G709A mutation may cause hearing impairment in combination with a synergistic effect of some other nuclear modifier genes.</p>

Sequence analysis of DFNB59 gene in a Chinese family with dominantly inherited auditory neuropathy / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate if the DFNB59 gene contributes to the hearing loss of a Chinese pedigree with dominantly inherited auditory neuropathy (AN).@*METHOD@#Nine members in four generations of the family were selected for this study. Genomic DNA was isolated from the peripheral leukocytes of the patients using the pure gene DNA isolation kits. Firstly, the subjects DNA fragment was PCR amplified using specific primers corresponding to exon 2 and 4 of the DFNB59 gene. Each fragment was purified and subsequently analyzed by direct sequencing in an applied biosystems 3730 automated DNA sequencer. The whole coding sequence of DFNB59 gene of one family patient were then PCR amplified and submitted for sequence analysis as described above. The resultant sequence data were compared with the standard sequence to identify deafness-associated mutations.@*RESULT@#PCR amplifications were successfully conducted in all the subjects. We failed to detect the presence either of mutations T54I and R183W in the exon 2 and exon 4 that have been reported, or any other deafness-associated mutations in the whole DFNB59 gene, by sequence analysis.@*CONCLUSION@#The DFNB59 gene seems not contribute to the pathogenesis of this Chinese AN family, which suggesting new gene(s) involvement.

Auditory neuropathy in deaf school students / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate incidents and clinical features of auditory neuropathy in Nanjing deaf school students.@*METHOD@#Three hundred and fifty-eight deaf students in the school accepted the first examination including otoscopic examination, tympanometry and transiently evoked otoacoustic emissions (TEOAE) screening. Detailed audiological and vestibular evaluations including pure-tone audiometry, immittance audiometry and acoustic reflex measures, transiently evoked otoacoustic emissions (TEOAE), distortion product otoacoustic emissions (DPOAE), auditory brain stem response (ABR), electronystagmography (ENG) and vestibular evoked myogenic potential (VEMP) were given to whom had positive TEOAE screening.@*RESULT@#Three hundred and twenty-three students entered the program of screening for auditory neuropathy. One student had positive TEOAE in single ear while the other two had positive TEOAE in both ears. In the screening stage,there were strong evidences in these three students with auditory neuropathy in the detailed audiological procedures.@*CONCLUSION@#Auditory neuropathy, which can also be found in deaf schools, is not as rare as we thought before. Early identification and intervention may help those children to avoid entering the deaf school and to return to normal society.

Sequence analysis of OTOF gene in a Chinese pedigree with autosomal dominant auditory neuropathy / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate if the OTOF gene contributes to the non-syndromic hearing loss of a Chinese pedigree with dominantly inherited auditory neuropathy (AN).@*METHOD@#The subjects included were 9 live individuals in an autosomal dominant AN pedigree, 3 sporadic AN patients and 3 normal-hearing controls. Genomic DNA was isolated from the peripheral leukocytes of the subjects using the Pure gene DNA Isolation Kits. Firstly, the whole coding sequence of OTOF gene of one family patient were PCR amplified using specific primers. Each fragment was purified and subsequently analyzed by direct sequencing in an Applied Biosystems 3 730 automated DNA sequencer. The resultant sequence data were compared with the standard sequence to identify deafness-associated mutations. Other DNA samples were then screened for these mutations by PCR amplification and sequence analysis.@*RESULT@#PCR amplifications were successfully conducted in all the subjects. Comparison of the resultant OTOF sequence in one family patient with the standard sequence identified 10 nucleotide variants which do not lead to amino acid change. These mutations were also detectable in other family individuals, 3 sporadic AN patients and 3 normal-hearing controls.@*CONCLUSION@#The OTOF does not seem to contribute to the pathogenesis of this Chinese AN family, which suggest new gene(s) involvement.