Mouse's Tale of Hope; Gene Research Breakthrough Could Help the Deaf to Hear
A MOUSE named Sebastian may hold the key to helping millions born deaf.
Scientists who have identified a rogue gene responsible for causing deafness have been able to make a healthy version in the laboratory.
Using genetic engineering technology they created hearing in Sebastian, and the next step is to extend trials of the technique to humans.
Sebastian's ancestors at the University of Michigan Medical School were deliberately made deaf 70 years ago. They were given X-rays which caused deafness mutations and these were passed down the lineage. None of the countless sub-
sequent generations of mice was able to hear.
After the mutated gene responsible was identified, experiments were carried out on eight fertilised mouse eggs.
One egg received the laboratory-manufactured healthy gene. It became Sebastian. He was born with hearing, unlike his parents and the seven others in the litter.
An enzyme dubbed Myo15 is at the centre of the new optimism.
Faults or mutations in its 'coding
instructions' spell deafness and the scientists now think they can overcome the mutation.
The scientists believe Myo15 transports a protein called actin to inner ear hair cell fibres during their development.
Sally Camper, associate professor of human genetics at the medical school, explained that the fibres move in response to changes in sound frequency 'like a field of wheat moves to changes of wind speed'. …