The gene machine that could decode you
Genome sequencing has revolutionised diagnosis of rare conditions and is set to radicalise treatments for the disease
READING the first-ever complete genetic blueprint for a human took 13 years of painstaking research. It was a scientific breakthrough on a par with splitting the atom and putting a man on the Moon.
Today, nearly 15 years on, cutting edge technology means sequencing the three billion letters of DNA that make up a human genome takes just three days.
And inside laboratories at the sprawling Wellcome Genome Campus near Cambridge, rows of sequencing machines are churning out new readings every 35 minutes.
It is one of the hottest areas of science and offers a ray of hope for thousands of people with undiagnosed rare conditions.
By providing a better understanding of what causes cancers, genome sequencing is also expected to radicalise treatments for the disease.
And thanks to the NHS’S 100,000 Genomes Project, Britain is leading the way. By the end of 2018, the project will have sequenced 100,000 genomes from 70,000 NHS patients.
It is the largest national sequencing project of its kind in the world and is the envy of scientists across the globe.
It is so successful that from April all NHS patients who could potentially benefit from sequencing will have access to the service. Patients with rare diseases may be offered a diagnosis where there wasn’t one before.
And there is the potential to improve survival rates for cancer patients through tailoring treatments to the specific genomic make-up of a patient’s disease.
“We are world leaders in doing this inside our NHS,” said Professor Mark Caulfield, chief scientist at Genomics England. And he revealed the 100,000 Genomes Project is already
saving lives. Prof He told of Mark Caulfield a couple who lost their son aged four months after he was born with a mysterious condition that led to constant infections.
Prof Caulfield said: “The boy’s mum and dad wanted to have more children but were scared of doing so.
“So we looked at the genomes of the deceased boy and his parents and found a change in the gene that makes a way of up taking vitamin B12 from the blood stream into cells.
“And that immediately explained why his immune system wouldn’t have been working. So within one week of being born, the NHS was able to test the second child. Sadly, the child was also affected but because we knew what the problem was that child has received weekly injections of vitamin B12 and so far is doing very well. “This is something that routine testing wasn’t able to detect, so without genome sequencing we would never have been able to change the outcome for that child.” And even where treatments are not yet available, genome sequencing is still making a difference to people’s lives. Prof Caulfield went on: “In one case we were able to bring a diagnosis to a man with an intellectual disability who was 29 and had still not achieved a diagnosis. “We explained to him why he is like he is. His sister was pregnant and there was a lot of anxiety she might have a child that was similarly affected. We were able to spot that this mutation had occurred only in him and wasn’t affecting any other family members.
“It isn’t necessarily going to lead to treatment, but it might pave the way for a treatment in the future.
“And if you talk to people affected by rare diseases all they want is not to have to go to yet another clinic to be told again that nobody knows what the cause of their problem is.”