For babies born with the rare genetic disorder phenylketonuria (PKU), their bodies are unable to break down a certain amino acid, which can lead to brain damage and seizures. If found early enough, however, PKU is easily treated, and children with the condition can go on to live a normal life. But sometimes, genetic testing for disorders such as this one come too late, and narrow windows of opportunity for treatment can close up for good.
But now, parents and physicians can have answers regarding a babys genetic abnormalities in only a few short days. Researchers from Childrens Mercy Hospitals & Clinics in Kansas City, Mo., have developed a new whole-genome sequencing technology capable of diagnosing genetic disorders in ICU newborns in just 50 hours a significantly less amount of time than the 12 to 14 days needed for current screening techniques.
The ability to diagnose infants in such a short amount of time could help to speed up available treatments as well as provide relief or knowledge to anxious parents.
There are about 500 diseases that can present in a baby for which theres a treatment, Dr. Stephen Kingsmore, director of the Center for Pediatric Genomic Medicine at Childrens Mercy Hospitals and Clinics and lead author of the study, told FoxNews.com. But for diseases that dont have treatment, this info can still be useful. It gives parents and physicians an answer. You can stop doing additional testing or stop giving futile treatments. Parents can get counseling about whether this can recur in a future child and get advice about how intense treatments can be.
Currently, there are more than 3,500 known genetic disorders conditions caused by a mutation in a single gene and the definitive method diagnose them is to sequence the mutated gene. However, a big problem with gene sequencing up until now has been knowing exactly which gene to sequence, according to the researchers. Each genome contains more than 3.1 billion nucleotides, and of those, three to four million variants exist. In order to diagnose a condition, all of those variants need to be analyzed a task that can take quite a long time.
To speed up this process, Kingsmore, along with fellow Childrens Mercy Hospital researcher Neil Miller, teamed up with the company Illumina a group dedicated to technologies that analyze genetic variations. Having announced in January the Illumina high-speed 2,500 a high-speed sequencing device, the company approached Kingsmore and Miller to develop software that would go hand-in-hand with their new instrument.
That was how SAGA and RUNE were born. After the Illumina high-speed 2,500 sequences the entire genome in less than 30 hours, the software applications then come into play. First, SAGA, which stands for sign-assisted genome analysis, helps physicians to determine which parts of the genome are significant depending on the patients symptoms.
It allows them to click on buttons of symptoms that are corresponding in the baby such as difficulty breathing, etc, Kingsmore said. The computer then matches those particular symptoms and signs to the right parts of the genome and selects of those 3,500 genetic diseases, which ones are appropriate to test. So it allows us to test the variants that are likely to cause a disease.
To determine how effective SAGA was in determining a diagnosis, the researchers used the program on over 500 previously diagnosed cases, and the software was 99 percent accurate in selecting the right gene according to the patients symptoms.
RUNE solves the second part of the puzzle, which is determining how these variants impact the gene in which they occur. Standing for rapid understanding of nucleotide-variant effect, RUNE essentially ranks the order of diseases that are on possibly on target for the variants that were found.
Original post:
New DNA test can diagnose genetic disorders in newborns in just 2 days
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