PurposeAutosomal recessive non-syndromic deafness (ARNSD) is characterized by a high degree of genetic heterogeneity with reported mutations in 58 different genes. This study was designed to detect deafness causing variants in a multiethnic cohort with ARNSD by using whole-exome sequencing (WES).MethodsAfter excluding mutations in the most common gene, GJB2, we performed WES in 160 multiplex families with ARNSD from Turkey, Iran, Mexico, Ecuador and Puerto Rico to screen for mutations in all known ARNSD genes.ResultsWe detected ARNSD-causing variants in 90 (56%) families, 54% of which had not been previously reported. Identified mutations were located in 31 known ARNSD genes. The most common genes with mutations were MYO15A (13%), MYO7A (11%), SLC26A4 (10%), TMPRSS3 (9%), TMC1 (8%), ILDR1 (6%) and CDH23 (4%). Nine mutations were detected in multiple families with shared haplotypes suggesting founder effects.ConclusionWe report on a large multiethnic cohort with ARNSD in which comprehensive analysis of all known ARNSD genes identifies causative DNA variants in 56% of the families. In the remaining families, WES allows us to search for causative variants in novel genes, thus improving our ability to explain the underlying etiology in more families.

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This investigation was carried out in the Audiology and Speech Pathology Section of the Department of Otorhinolaryngology of Hacettepe University. The pregnant group comprised of 20 women followed by the Department of Gynaecology and Obstetrics of the same university; 18 non-pregnant women comprised the control group. The aim of this investigation was to study the relationship between hormonal changes in pregnancy and cochlear functions. All subjects underwent ENT examination, audiologic and acoustic immitance measurements and auditory brain stem response (ABR) tests. Results from each trimester and post-partum period of the pregnant group were compared. These results demonstrated that there was a decrease in hearing levels for 125 Hz, beginning in the first trimester and increasing in the second and third trimesters. Hearing returned to normal in the post-partum period. Similar findings were also obtained for 250 and 500 Hz; however, frequencies higher than 500 Hz demonstrated no significant correlation. Uncomfortable loudness was statistically significant between the third trimester and post-partum period. ABR tests did not reveal any differences. In conclusion, there is a low-frequency hearing loss and tolerance problem in pregnancy mimicking cochlear pathology. However, this hearing loss did not reach pathologic levels in any case and returned to normal in the post-partum period.

Our preliminary results show that there is adequate contribution of brainstem implants in the development of auditory-verbal skills. Additional handicaps slow the progress of the prelingually deaf children.

On the 18th of September 2009, a group of health care professionals and scientists involved in implantation of the auditory system attended a meeting convened by the Hacettepe Cochlear Implant Group. The aim of the meeting was to have a detailed discussion on the pressing and pertinent issues around auditory brainstem implantation (ABI) in children and in non-neurofibromatosis Type 2 (NF2) cases and to reach a consensus based on these discussions. surgery, experience of individual ABI centers, intraoperative issues, and rehabilitation with the final session devoted to discussion of the issues raised. The centers presented their experience of ABI in children who had hearing impairment because of congenital abnormalities or pathology where cochlear implantation (CI) was either contraindicated or the possibility of successful placement of the electrode was unlikely. Altogether, 61 children with various types of inner ear malformations, cochleovestibular nerve (CVN) anomalies, cochlear ossification, and bilateral cochlear fractures with cochlear nerve avulsion were presented by different groups. The following topics were discussed, and a consensus was obtained at the end of the meeting on the following issues. IN WHICH CHILDREN AND NON-NF2 PATIENTS IS THE ABI A VIABLE INTERVENTION?Two patient categories were identified: 1) Prelingual patients with inner ear malformations and cochlear nerve hypoplasia/aplasia. ABI provides auditory perception in most patients. The potential for speech and language acquisition in the longer term will depend on the age of implantation, the presence or absence of additional disabilities, and the other established factors seen in CI. It also was concluded that open set speech discrimination is possible in selected cases. In addition, prelingually deafened children because of meningitis with total ossification of both cochleas also should be included in this group. 2) Individuals deafened postlingually because of meningitis, temporal bone fractures with cochlear nerve avulsion, otosclerosis with gross cochlear destruction, or unmanageable facial nerve stimulation with CI. As with CI, the duration of severe or profound deafness is a prognostic indicator, and with short