Genetic link to deafness in old age found

Researchers in Belgium have linked fault in a specific gene to age-related hearing loss. Changes in a gene called KCNQ4 are responsible for some hearing loss in the elderly, according to the researchers. Hearing loss has often been thought of as an age-related process - linked to exposure to noise over a lifetime - rather than a genetic one.

The researchers, based at the University of Antwerp, found that 'minor, but definite' alterations in the KCNQ4 gene were more common in elderly people who complained of hearing loss. The research was part of the Human Mutation study, which involved more than 1,200 elderly people - it was funded by the Royal National Institute for Deaf People (RNID).

Previously, research has shown that mutations in the gene can be linked to hereditary hearing loss earlier in life. In the latest study, the researchers were looking at hearing loss in people aged between 40 and 80 years old. They studied the DNA of the subjects and detected three gene variations, known as SNPs (where a single 'letter' of the DNA code has changed) in the people with hearing loss, which were not present in people with normal hearing. The researchers say that more detailed studies are needed to follow up these findings, to see exactly what hearing changes are caused by the respective mutations.

Dr Ralph Holme, the RNID's Biomedical Research Manager, said that many people consider loss of hearing to be an 'inevitable' part of getting older, rather than 'a potentially preventable condition'. He continued: 'This research provides another important piece of the jigsaw in highlighting a gene associated with age-related hearing loss', adding that the research 'offers real hope that treatments will be found and we are optimistic that in the future people will no longer face the prospect of losing their hearing as they age'.