Monthly Archives: Outubro 2015

Next-generation genetic sequencing found right diagnosis for Australian ‘Mystery Boy’

Mystery Boy Brandon Keesing was incorrectly diagnosed with a degenerative muscular disease until revolutionary genetic sequencing gave him life-changing news.

 

Originally thought that Keesing has a mitochondrial disease, doctors had been wrong all along. Revolutionary advances in genetic sequencing proved he did not have mitochondrial disease at all. “In recent years the capacity to read the genetic code of every single gene — all 20,000 of them in the human body — has reached a point where it is now efficient, accurate, cost-effective to be able to do this,” he says.

 

The new technique is called “next generation sequencing” — and where previously it took weeks or months to analyse the code of a single gene, today laboratory computers can decode all 20,000 genes in one go.

 

Almost immediately Westmead Children’s Hospital researchers could pinpoint which one of Brandon’s genes had a mutation. Professor Christodoulou illustrates how the technique works on a chart. “So here in the unaffected individual we have an ‘A’. Here in the affected individual we have a ‘G’. And that’s precisely where the mistake is,” he says.

 

Doctors using next generation sequencing discovered in fact that Brandon had congenital myasthenia — a different genetic disease which also affects the muscles. But although incurable, it is not usually fatal and can be treated with medication.

 

“The name of the gene that we found the mistakes in is called COLQ, and it has a completely different role,” Professor Christodoulou says. “It has nothing to do with mitochondrial energy production. “What it is involved in is co-ordinating the communication of nerve cells with the muscle, so that the muscle, when it receives an impulse from a nerve cell, it contracts and relaxes appropriately.

 

“So the problem with the COLQ mistakes is that this process couldn’t be co-ordinated properly. And that’s what actually led to his progressive problems.”

 

Finding that one gene in 20,000 has transformed Brandon’s life. A simple drug quickly restored some of his muscle strength. As quickly as he had deteriorated as a toddler, he suddenly began making huge strides.

“We noticed it straight away. By the end of that week he got up off that bed and he walked,” she says, wiping away tears. “That was unreal. I’ll never forget that day. I was so happy for him and … I just knew from that he was going to grow, he was going to enjoy his life that much more than what he had before. And he has.”

 

Professor Christodoulou says it was a very gratifying outcome for doctors.

Sourced through Scoop.it from: www.abc.net.au

Quem diria, com a redução de preço das novas tecnologias de sequenciação foi possível diagnosticar correctamente a doença desta rapaz ?

See on Scoop.itBioinformática

CRISPR tweak may help gene-edited crops bypass biosafety regulation

Technique deletes plant genes without adding foreign DNA.

Source: www.nature.com