Homing in on hereditary deafness

Maternally inherited nonsyndromic deafness is caused by a defect in mitochondria—the organelles within cells in which respiration and energy production occur—and can cause premature deafness in humans.

Now, a team of Yale scientists led by Gerald S. Shadel, Ph.D., professor of genetics, has shed light on the dysfunction and found a potential target for future therapies.

The researchers genetically altered mice to model mitochondrial deafness, in which hearing loss was caused by dysfunction in specialized tissues in the inner ear. The team found that activation of the stress-response enzyme AMPK triggered this dysfunction. They also found that genetically reducing AMPK activity had no impact on mice with normal hearing, but inhibited hereditary hearing loss in the deafness-model mice.

The study, published in The American Journal of Pathology in December, points to possible strategies for preventing or treating deafness associated with mitochondrial dysfunction and aging in humans.