Scientists have successfully created a 'golden ear' mouse with great hearing as it ages by crossing a mouse with poor hearing and a mouse with even worse hearing.
University of Rochester Medical Center scientists focussing on age-related hearing loss, or presbycusis, have for the first time created the mouse equivalent of a person with "golden ears" - people who are able to retain great hearing even as they grow older.
The new mouse is expected to offer clues about how such people could retain outstanding hearing even through old age. It has been extimated that almost 5 percent of people, mainly women, fall into this category.
The new mice, created in the laboratory of Dr. Robert Frisina, embody many of the same traits of human "golden ears" because of an astute cross of two types of mice long popular with researchers.
The team started with the rodent gold standard of age-related hearing loss, CBA mice, which lose their hearing much like aging people do, with both the ears and the brain degenerating in sync.
Then the team added C57 mice, not only for their breeding abilities but because they experience hearing loss in a different way, at an even younger age.
By crossing the two, the team was able to create a mouse with an aging brain but with good, young ears - the mouse equivalent of golden ears.
The mouse also gives researchers a new tool to explore protective factors that allow some organisms to retain outstanding hearing for their whole lives, rather than focusing on the factors that contribute to hearing loss.
"This allows us to really take a detailed look at good hearing in old age. Which chemical pathways are most active, for instance? This is about what goes right with age, not what goes wrong. These mice have the hearing of a young adult. Understanding why should help us understand more about how a person's hearing changes as he or she ages," said Frisina.
"This new mouse also opens up a new, clear window into the aging brain. It really allows us to look at the auditory systems in the brain in a very pure way, without distortion from the ear," he added.
The study was published online recently in the journal Neurobiology of Aging.