Prevenção de surdez (edição genética)

https://www.theguardian.com/science/2017/dec/20/breakthrough-for-genetic-hearing-loss-as-gene-editing-prevents-deafness-in-mice

Citando:
"Deafness has been prevented in mice using gene editing for the first time, in an advance that could transform future treatment of genetic hearing loss.

The study found that a single injection of a gene editing cocktail prevented progressive deafness in baby animals that were destined to lose their hearing.

“We hope that the work will one day inform the development of a cure for certain forms of genetic deafness in people,” said Prof David Liu, who led the work at Harvard University and MIT.

Nearly half of all cases of deafness have a genetic root, but current treatment options are limited. However, the advent of new high-precision gene editing tools such as Crispr has raised the prospect of a new class of therapies that target the underlying problem."

(...)

"The study, published in the journal Nature, focused on a mutation in a gene called Tmc1, a single wrong letter in the genetic code, that causes the loss of the inner ear’s hair cells over time.

The delicate hairs, which sit in a spiral-shaped organ called the cochlea, vibrate in response to sound waves. Nerve cells pick up the physical motion and transmit it to the brain, where it is perceived as sound."

Surdez revertida por terapia de genes (em ratos)

http://www.bbc.com/news/health-38881369
O artigo tem uma foto muito interessante dos defeitos nos pelos envolvidos na audição que estando desordenados tornam as pessoas (neste caso, os ratos) surdas.
Citando:
"Studies, published in Nature Biotechnology, corrected errors that led to the sound-sensing hairs in the ear becoming defective.
The researchers used a synthetic virus to nip in and correct the defect.
"It's unprecedented, this is the first time we've seen this level of hearing restoration," said researcher Dr Jeffrey Holt, from Boston Children's Hospital.
About half of all forms of deafness are due to an error in the instructions for life - DNA.
In the experiments at Boston Children's Hospital and Harvard Medical School, the mice had a genetic disorder called Usher syndrome.
It means there are inaccurate instructions for building microscopic hairs inside the ear.
In healthy ears, sets of outer hair cells magnify sound waves and inner hair cells then convert sounds to electrical signals that go to the brain.
The hairs normally form these neat V-shaped rows."
(...)
"There are about 100 different types of genetic defect that can cause hearing loss. A different therapy would be needed for each one.
Dr Holt told the BBC News website: "We've really gotten a good understanding of the basic science, of the biology of the inner ear, and now we're at the point of being able to translate that knowledge and apply it to human patients in the very near future."
One of the big questions will be whether the synthetic virus is safe.
It was based on adeno-associated virus, which has already been used in other forms of gene therapy.
The researchers also want to prove the effect is long-lasting - they know it works for at least six months.
There are also questions about the "window of opportunity". While the therapy worked in mice treated at birth, it failed when given just 10 days later.'