Detection of 35delG, 167delT mutations in the connexin 26 gene among Egyptian patients with nonsyndromic sensorineural hearing loss

Aim The aim of this study was to detect 35delG and 167delT mutations in the connexin 26 gene among Egyptian patients with nonsyndromic sensorineural hearing loss, allowing accurate diagnosis, proper genetic counseling, and carrier detection. Patients and methods Fifty-one patients were subjected to 35delG and 167delT mutations detection using PCR-based techniques. Results Seven patients had the 35delG mutation. Four patients were homozygous and four patients were heterozygous for this deletion. Two homozygotes were sibs and two heterozygotes were sibs as well. The allelic frequency for 35delG was 10.8%. The 167delT was not detected in any of the patients studied. Conclusion The 35delG is a common pathogenic mutation and an important contributor toward autosomal recessive nonsyndromic hearing loss in the Egyptian population.

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