A Dubai hospital has introduced a method to sequence the genetic material of critically ill children suspected of having inherited conditions – saving time and giving more accurate diagnoses.
Through a programme called Little Falcon, Al Jalila Children’s Hospital is carrying out rapid whole-genome sequencing (rWGS), which sequences a patient’s genetic material in a few days.
Now more affordable than it once was, the technology is also often faster than the previous approach, which could involve several genetic tests.
It means that infants and older children admitted to intensive care units can have their genetic material sequenced within days, enabling doctors to quickly decide on the best treatment.
Researchers and clinicians have highlighted the technology’s benefits in a study published in the journal Nature Genetics that involved rWGS in 100 children from 18 Middle Eastern and Asian countries. Most of them were Dubai residents, and the vast majority were less than a year old.
One of the study’s authors, Prof Ahmad Abou Tayoun of Mohammed Bin Rashid University of Medicine and Health Sciences and director of Dubai Health’s Genomic Medicine Centre, said the previous approach had been to carry out sequential tests with “lower yield technologies”.
This often involved looking for particular abnormalities, which could cause delays if the wrong test was used.
“If a patient has the right mutation and the right test is used, then they get an answer. Otherwise they go back and start again. The process can take weeks or months,” he said.
“In rapid whole genome sequencing, we can capture comprehensive mutation types across the whole genome [all genes], and within three to four days.”
Since the first use of rWGS at the hospital five years ago, it has been increasingly adopted and has become standard for diagnosing children with suspected genetic conditions.
Dr Shiva Shankar, a neonatal consultant at the hospital, said rWGS could make a diagnosis “far faster” than numerous tests.
“This has several clinical benefits, including earlier diagnosis and earlier guidance of clinical management, often leading to personalised care trajectories and altered disease outcomes,” he said.
The new testing regimen is offered to children who arrive in the neonatal or paediatric intensive care units with an illness of unknown cause and with features suggesting it may be caused by a mutation in a single gene.
These features include very low muscle tone, persistent seizures, abnormal electrical activity in the brain and a family history of genetic disease.
In the study, rWGS gave a clear diagnosis in 53 per cent of patients, compared with 30 per cent using the previous approach. Of the patients who had not undergone rWGS, 23 per cent required multiple tests.
Reduced cost of the technology
The technology has become more attractive in part because of cost reductions. Several years ago, Prof Abou Tayoun said, the average cost was about $9,200 a patient, whereas now it typically ranges between $3,500 and $4,500.
The first draft sequence of the human genetic material was published in 2001 and, according to the National Human Genome Research Institute in the US, is about $300 million to produce. The first sequence of a single individual’s genetic material was released in 2007.
While costs have fallen, the complexity of deploying rWGS was the key reason it had not become the standard approach until recently.
As well as needing a well-established neonatal or paediatric intensive care unit and expertise in genomics, it requires multiple specialists, all operating under an accredited framework. In the case of Al Jalila Children’s Hospital, that is the College of American Pathologists.
“The operational cost of rWGS, though still higher than standard testing, has been declining steadily,” Prof Abou Tayoun said.
“That, combined with rWGS’s higher diagnostic yield, clinical utility, and reduced time-to-diagnosis, can translate into economic benefits that offset the additional operational costs and justify early investment.”
Prof Abou Tayoun said that, until now, rWGS had mostly been restricted to the US and Europe, with much of the work carried out for research purposes.
“As Dubai’s first integrated academic health system, Dubai Health is uniquely positioned to translate genomic science into frontline care at scale, reaching every critically ill infant and child. This integrated model of care makes this programme possible,” he said.
