American scientists say that a protein deep in the ear is crucial for normal hearing - they say this protein could be the
route for treating and curing an enormous number of deaf people.
A team of scientists from Harvard Medical School, USA, say there is a protein on the tips of the hair cells of the inner ear
- TRPA1 - which allows the conversion of sound waves (vibrations) into the electrical impulses, these are then processed by
the brain.
You can read about this animal study in the journal Nature.
When we hear, sound waves vibrate the eardrum. As soon as the eardrum vibrates, the ossicles (tiny bones) start to move.
The vibrations continues into the oval window (very thin tissue located at the entrance of the inner ear). Wave like motions
that take place in a fluid in the cochlea (looks like a little snail). In the cochlea there are thousands of tiny hair
cells, these are connected to nerves. The nerves pass electrical impulses to the brain which processes the information, and
so we 'hear'.
We have never understood how these tiny hair cells can convert sound waves into signals that reach the brain (electrical
signals). It seems that now, maybe we do.
The scientists at Harvard, after experimenting with mice and zebrafish, say the protein TRPA1 allows this conversion to
happen,
TRPA1 resides on the very tips of these tiny hair cells. Hair cells that did not have TRPA1 on their tips did not convert
the vibrations into electrical impulses, i.e. mice/zebrafish whose hair cells had no TRPA1 were deaf.
Dr. Corey, study leader, said further studies were needed. He said "People have been looking for this protein for decades.
It is the strongest evidence yet that this protein is the hair-cell transducer channel."
Specialists say this could eventually be the route for helping many deaf people to hear.