Document Type : Original Article


1 Department of Otolaryngology and Skull Base Surgeon, College of Medicine, Ibn Sina University of Medical and Pharmaceutical Sciences, Baghdad, Iraq

2 Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, USA

3 Department of Orthopaedic Dentistry, A. I. Evdokimov Moscow State University of Medicine and Dentistry, Moscow, Russia

4 Department of Agronomy and Plant Breeding, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran


Deafness can occur due to damage to the ear, especially the inner ear. In other cases, the cause is a heterogeneous genetic abnormality and is caused by the changes that occur in the genes involved in the hearing process. Mutations in GJB2 and SLC26A4 genes are one of the most important causes of deafness in the world, which causes syndromic and non-syndromic hereditary hearing loss. The purpose of this study is to investigate GJB2 and SLC26A4 genes related to genetic syndromes of deafness and bioinformatic analysis at the genome and proteome level and to evaluate and compare the expression of these genes in different tissues of the human body. For this purpose, tools related to bioinformatics analysis such as UCSC and OMIM databases were used. One of the common genetic syndromes caused by mutations in these genes is pendred syndrome. The clinical symptoms of this disease are weight gain, constipation, dry skin, and hair, decreased energy, sleepiness, bulging belly, decreased body temperature, and slow growth. This disease does not currently have a specific treatment, so it is very important and fundamental to investigate the genetic factors affecting this disease. The results of this research showed that the transfer of potassium, sodium, and chlorine ions as well as the mutation in the SLC26A4 gene, which is responsible for the synthesis of pendrin protein, is very effective in the occurrence of pendred syndrome. To diagnose pendred syndrome more accurately, molecular methods should be used in genetic tests. The results of comparing the expression profiles of these two genes showed that the difference in the expression of these two genes is very high and, in general, the expression of the SLC26A4 gene in the body is very low. Because people with hearing loss have other problems including damage to other parts of the body such as the heart, kidneys, or eyes. Knowing the genetic cause in these cases allows the doctor to be aware of problems in other systems as well.

Graphical Abstract

Investigation of GJB2 and SLC26A4 genes related to pendred syndrome genetic deafness patients


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ِDr. Haider Majid Al-Zaidi
Ibn Sina university of Medical and Pharmaceutical Sciences
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