MedGenome Labs, a genomics-based research and diagnostics company, offers genetic testing for couples with a family history of hearing loss.
Awareness and early detection are the only ways to prevent genetic hearing loss disorders from being passed down to next generations.
Couples should undergo pre-conception counselling with a genetic counsellor, especially when there is positive family history for a disorder. Such counselling sessions help the couple better understand the risk to the child as well as help recommend a suitable prenatal genetic test, according to Dr Sunitha Tella, head, Clinical Genetics and Fetal Medicine Department, Institute of Genetics and Hospital for Genetic Diseases, Hyderabad.
“In one such case, the first born child had cognitive disorders. It was recommended, to understand if the hearing impairment was due to genetic factors basis, which appropriate screening measures could be taken when they plan a second child,” she said. Dr Tella suggested the family to undergo genetic testing at MedGenome Labs, Bengaluru.
The blood samples of the parents and their first child revealed their first born had two mutations or variants in the GJB2 gene, which is associated with hearing loss, while the parents were found to be carrying one mutation each, making them ‘carriers’ of the disease. This meant that their child may have 25 per cent chance of being affected with hearing impairment.
The foetus was tested for these two variants and was found that it was only harbouring one of the two mutations found in the first child. In this case the child would be a carrier of the disease and wouldn’t suffer from hearing loss, she added.