Genome sequencing is set to revolutionise the diagnosis of rare childhood conditions, according to researchers in Cambridge.
All seriously ill children in England with an unexplained disorder will be eligible for genome analysis, which involves mapping a person’s entire genetic code, from next year.
It follows a project at Addenbrooke’s Hospital and Cambridge university.
One in four children in intensive care had a genetic disorder, it found. Researchers were able to give a diagnosis within two to three weeks, which sometimes led to a change in treatment or spared children further invasive tests. In each case, the whole genome of the child and both their parents were sequenced, which showed whether a gene fault had been passed on.
So far, about 350 babies and children in intensive care at Addenbrooke’s Hospital have had their genome, made up of billions of letters of DNA code, analysed as part of the Next Generation Children research project.
In two-thirds of cases, the gene error had occurred spontaneously at conception rather than being inherited. The children had a range of conditions – including birth abnormalities, neurological symptoms including epilepsy, metabolic diseases or reduced growth.
Lucy Raymond, professor of medical genetics and neurodevelopment at the University of Cambridge, who led the project, said: “It is astonishing to be able to give a meaningful result from whole genome sequencing analysis in just a couple of weeks, compared to earlier in my career, when we spent years simply trying to locate a single gene.”
One surprising finding was that a child’s appearance and clinical symptoms alone were rarely a good predictor of whether they had a genetic condition.
Prof Raymond said the project would be used as a template by the NHS Genomic Medicine Service and rolled out across England in 2020. This will mean that any baby or child in England admitted to intensive care with an unexplained condition will be eligible, together with their parents, for whole genome sequencing – the first national health service in the world to offer this.