|LETTER TO EDITOR
|Year : 2015 | Volume
| Issue : 2 | Page : 150
Hearing loss prevalence and risk factors among Iranian deaf children: The first report from Iran
Mahmood Dhahir Al-Mendalawi
Department of Paediatrics, Al-Kindy College of Medicine, Baghdad University, Baghdad, Iraq
|Date of Web Publication||6-Apr-2015|
Prof. Mahmood Dhahir Al-Mendalawi
P.O. Box 55302, Baghdad Post Office, Baghdad
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Al-Mendalawi MD. Hearing loss prevalence and risk factors among Iranian deaf children: The first report from Iran. J Clin Neonatol 2015;4:150
|How to cite this URL:|
Al-Mendalawi MD. Hearing loss prevalence and risk factors among Iranian deaf children: The first report from Iran. J Clin Neonatol [serial online] 2015 [cited 2020 Apr 5];4:150. Available from: http://www.jcnonweb.com/text.asp?2015/4/2/150/154550
I read with interest the study by Amirsalari et al.  on the hearing loss prevalence and risk factors among Iranian deaf children who were a candidate for cochlear implantation. Amirsalari et al.  addressed in their study that no considerable risk factors for sensorineural hearing loss were noticed in 29.7% of the studied cohort compared to 70.3% with obvious risk factors. Among 70.3%, 33% were considered to be hereditary deafness cases based on the presence of one or more close deaf relatives in the family and positive marital consanguinity among the parents of deaf children. It is well-known that hereditary hearing loss is a very common disorder. When inherited in an autosomal recessive manner, it typically presents as an isolated finding. Interestingly and unexpectedly, in spite of extreme heterogeneity, mutations in one gene, GJB2, are the most common cause of a congenital severe-to-profound deafness in many different populations.  The prevalence of GJB2 mutation has been extensively investigated among Iranian deaf children, and it was reported to be 14.3-16.4% with c. 35delG being the most prevalent mutation. , Though mutational analysis was not contemplated among the studied cohort in Amirsalari et al. study,  I presume that the reported 33% hereditary deafness cases were actually autosomal recessive nonsyndromic hearing loss due to GJB2 mutations. This two-fold increase in the prevalence of GJB2 mutations among the studied Iranian deaf children compared with 14.3-16.4% reported previously , is alarmingly high. Based on the observation that treatment response in children with the homozygous 35delG mutation was found to be better than in heterozygous patients, and treatment response in children with the mutation was better than in children with no mutation, mutation screening for finding deafness causing mutations in the GJB2 gene could be considered a useful predictor of postcochlear implantation speech perception and production. 
| References|| |
Amirsalari S, Saburi A, Radfar S, Yousefi J, Nouhi S, Hassanalifard M, et al
. Hearing loss prevalence and risk factors among Iranian deaf children: The first report from Iran. J Clin Neonatol 2014;3:191-4.
Najmabadi H, Nishimura C, Kahrizi K, Riazalhosseini Y, Malekpour M, Daneshi A, et al.
GJB2 mutations: Passage through Iran. Am J Med Genet A 2005;133A:132-7.
Peyvandi A, Morovvati S, Rabiee H, Ranjbar R, Ajalloueyan M, Hassanalifard M. Detection of the GJB2 mutation in Iranian children with hearing loss treated with cochlear implantation. Balkan J Med Genet 2011;14:19-24.
Bonyadi MJ, Fotouhi N, Esmaeili M. Spectrum and frequency of GJB2 mutations causing deafness in the northwest of Iran. Int J Pediatr Otorhinolaryngol 2014;78:637-40.