Genetic patch cures deafness in newborn mice
London, Feb 5 : A tiny "genetic patch" can be used to prevent a form of deafness that runs in families, a new research has shown.
Patients with Usher syndrome have defective sections of their genetic code which cause problems with hearing, sight and balance.
A study showed the same defects could be corrected in mice to restore some hearing, the BBC reported.
Experts said it was an "encouraging" start.
There are many types of Usher syndrome tied to different errors in a patient's DNA - the blueprint for building every component of the body.
One of those mutations runs in families descended from French settlers in North America.
When they try to build a protein called hormonin, which is needed to form the tiny hairs in the ear that detect sound, they do not finish the job.
It results in hearing loss at birth and has a similar effect in the eye where it causes a gradual loss of vision.
Scientists at the Rosalind Franklin University of Medicine and Science, in Chicago in the US, designed a small strip of genetic material which attaches to the mutation and keeps the body's factories building the protein.
There has been something of a flurry of developments in restoring hearing in the past year.
It suggests that the future of hearing loss may be more than just hearing aids and cochlear implants.
Stem cells restored hearing in deaf gerbils, a drug could produce new sound sensing hairs in mouse ears, a genetically modified virus led to deaf mice recovering some hearing and now a genetic patch has done the same.
Far more research will be needed if any of these are to be adapted for people.
However, they represent a series of landmark moments in attempts to cure deafness.
When mice with Usher syndrome were injected with the "genetic patch" they grew up able to hear and had no balance problems.
For the first couple of months their hearing was close to normal in the lower frequencies, but had started to deteriorate by six months.
The researchers do not know if this is because the patch needs to be in place during early development in order to make a difference or if the patch struggles to make it into the inner ear beyond a certain point.
This could raise problems in designing a similar treatment in people. Humans spend far longer in the womb than mice meaning any treatment might need to be given before a baby is born.
The study is published in the journal Nature Medicine.