A Study On GJB2 And GJB6 Gene Mutations Among Malays With Non-Syndromic Hearing Loss
Loading...
Date
2010-05
Authors
Zainal, Siti Aishah
Journal Title
Journal ISSN
Volume Title
Publisher
Universiti Sains Malaysia
Abstract
Hearing loss is the most common congenital sensory defects in human. About one in a thousand newborn in the world is born with the abnormality, which may vary from mild level of hearing loss to profound loss. This loss can be caused by two factors, genetic and environmental factors and more than 50% of the defect is due to genetic causes. It has been proven that multi genes are involved in non-syndromic hearing loss (NSHL), a type of hearing loss without other symptoms and covered in this study. Mutations in GJB2 gene have been shown to be a major role for congenital NSHL. A related gene, GJB6 which is located adjacent to GJB2 might be related and associated with NSHL. The objectives of this study are to identify the mutations in the two genes and study the association with NSHL. A total of 91 buccal cell samples of NSHL patients and 91 normal volunteer buccal cells samples in Kelantan were taken for this study. Polymerase chain reaction (PCR) was used to amplify the coding region of GJB2 gene. The PCR product of GJB2 coding region was preceded with screening for mutations using denaturing High Performance Liquid Chromatography (dHPLC) and mutations detected were confirmed by DNA sequencing. Eleven sequence variations including mutations and polymorphisms were found in 32 patients and 37 control subjects after 182 NSHL patients and controls were screened. However, all the variations did not show any statistically significant association with NSHL and the severity. For GJB6 gene coding region, the deletion was identified by multiplex PCR assay whereby β-globin gene was used as internal control. All 182 patients and controls were found to have no deletion of GJB6 coding region irrespective of whether they have genetic variation in GJB2 or not. Consequently, it is believed that a larger sample size and screening all regions in GJB2 and GJB6 and other related genes are necessary to verify the possible association between the mutations and polymorphisms and the severity of hearing loss in patients
Description
Keywords
Hearing loss is the most common , congenital sensory defects in human