terça-feira, 7 de fevereiro de 2017

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.'