Journal of Basic Research in Medical Sciences
J Basic Res Med Sci
Volume 13, Issue 2 (4-2026)
jbrms 2026, 13(2): 19-30 |
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Bakhshipour P, Karami M, Keshavarzi F. Investigation of the Frequency of 167delT Mutations of Gap Junction Protein Beta 2 (GJB2) Gene in the Deaf Population of Non-Syndromic West of Iran. jbrms 2026; 13 (2) :19-30
URL: http://jbrms.medilam.ac.ir/article-1-1017-en.html
URL: http://jbrms.medilam.ac.ir/article-1-1017-en.html
Department of Biology, Sa.C., Islamic Azad University, Sanandaj, Iran , gol.keshavarzi@gmail.com
Abstract: (289 Views)
Introduction: Deafness is one of the most common sensory-neural disorders, with 80% of hereditary deafness being non-syndromic. The aim of this study was to investigate the frequency of the 167delT mutation of the gap junction protein beta 2 (GJB2) gene in the deaf population of non-syndromic West Iran.
Materials & Methods: Seventy individuals were included in the study, with 34 being deaf and 36 being healthy. The RFLP-PCR technique was used to detect the 167delT mutation.
Results: The frequency of the homozygous mutant 167delT was 5.7% (4 individuals, equivalent to 8 chromosomes), with the heterozygous carriers at 75.7% (53 individuals, equivalent to 106 chromosomes), and the homozygous genotype in healthy individuals was 18.6% (13 individuals, equivalent to 26 chromosomes). In deaf individuals, the frequency of the homozygous mutant 167delT was 5.7% (4 individuals, equivalent to 8 chromosomes), the heterozygous genotype was 39.6% (27 individuals, equivalent to 54 chromosomes), and the frequency of the wild-type homozygous genotype was 4.7% (3 individuals, equivalent to 6 chromosomes). In healthy individuals, there was zero mutant genotype, 36.1% heterozygous carriers (26 individuals, equivalent to 52 chromosomes), and 13.9% wild-type homozygous (10 individuals, equivalent to 20 chromosomes).
Conclusion: Gene mutations play a role in causing non-syndromic autosomal recessive deafness in our statistical population from Kermanshah Province. The GJB2 167delT mutant is responsible for 5.7% of ARNSHL deafness in the population of Kermanshah, which differs from the rates reported in other parts of Iran.
Materials & Methods: Seventy individuals were included in the study, with 34 being deaf and 36 being healthy. The RFLP-PCR technique was used to detect the 167delT mutation.
Results: The frequency of the homozygous mutant 167delT was 5.7% (4 individuals, equivalent to 8 chromosomes), with the heterozygous carriers at 75.7% (53 individuals, equivalent to 106 chromosomes), and the homozygous genotype in healthy individuals was 18.6% (13 individuals, equivalent to 26 chromosomes). In deaf individuals, the frequency of the homozygous mutant 167delT was 5.7% (4 individuals, equivalent to 8 chromosomes), the heterozygous genotype was 39.6% (27 individuals, equivalent to 54 chromosomes), and the frequency of the wild-type homozygous genotype was 4.7% (3 individuals, equivalent to 6 chromosomes). In healthy individuals, there was zero mutant genotype, 36.1% heterozygous carriers (26 individuals, equivalent to 52 chromosomes), and 13.9% wild-type homozygous (10 individuals, equivalent to 20 chromosomes).
Conclusion: Gene mutations play a role in causing non-syndromic autosomal recessive deafness in our statistical population from Kermanshah Province. The GJB2 167delT mutant is responsible for 5.7% of ARNSHL deafness in the population of Kermanshah, which differs from the rates reported in other parts of Iran.
Type of Study: Research |
Subject:
Medical genetics
Received: 2025/08/8 | Accepted: 2026/01/7 | Published: 2026/04/6
Received: 2025/08/8 | Accepted: 2026/01/7 | Published: 2026/04/6
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