A large research project is decoding the DNA of hundreds of infants in US. But should it do so and how far will it go?
Little Amelia Sloan is a pioneer: Shortly after her birth,scientists took drops of the healthy babys blood to map her genetic code.
Amelia is part of a large research project that is decoding the DNA of hundreds of infants. New parents can soon start signing up for smaller studies to explore if whats called genome sequencing fully mapping someones genes to look for health risks should become a part of newborn care.
Its full of ethical challenges.
Should parents be told only about childhood threats? Or would they also want to learn if their babies carried a key gene for,say,breast cancer after they are grown? Could knowing about future risks alter how a family treats an otherwise healthy youngster? And how accurate is this technology could it raise many false alarms?
This is the newest frontier in the genetic revolution: how early to peek into someones DNA,and how to make use of this forecast without causing needless worry.
This was something that was looming over the horizon, said Dr Alan Guttmacher,a paediatrician and geneticist at the National Institutes of Health. Last month,the NIH announced a $25 million,five-year pilot project in four cities Boston,San Francisco,Chapel Hill,and Kansas City to start answering some of the questions before the technology is widely offered for babies.
Today,the four million US babies born annually have a heel pricked in the hospital,providing a spot of blood to be tested for signs of at least 30 rare diseases. This newborn screening catches several thousand affected babies each year in time for early treatment to prevent death,brain damage or other disabilities. Its considered one of the nations most successful public health programmes.
A complete genetic blueprint would go well beyond what that newborn blood spot currently tells doctors and parents allowing a search for potentially hundreds of other conditions,some that arise in childhood and some later,some preventable and some not.
If I truly believed that knowing ones genome was going to be transformative to medicine over the next decade or more,then wouldnt I want to start generating that information around the time of birth? asked Dr John Niederhuber,former director of the National Cancer Institute who now oversees one of the largest baby-sequencing research projects to date.
At Niederhubers Inova Translational Medicine Institute in Falls Church,Virginia,researchers are mapping the genomes of newborns,along with their parents and other relatives for comparison. The long-term goal of the privately funded study is to uncover genetic patterns that predict complex health problems,from prematurity to developmental disorders.
But the experimental tests will turn up some gene mutations already well-known to cause serious ailments,and participating parents must choose upfront whether to be told. They dont get a full report card of their babys genes. Only ones that cause treatable or preventable conditions so-called medically actionable findings are revealed,to the familys doctor. That means in addition to paediatric diseases,parents also could learn whether a baby carries a breast-cancer-causing gene,information useful once she reaches young adulthood.
Nurse Holly Sloan was eager to enroll daughter Amelia,although she thought hard about how shed handle any bad news.
If it was something that we could hopefully prevent through diet or exercise or some kind of lifestyle change,we could start with that as early as possible, said Sloan. I guess Im just the type of person,I would rather know and address it. Five months after Amelias birth,she hasnt gotten any worrisome results.
Until now,genome sequencing has been used mostly in research involving curious adults or to help diagnose children or families plagued by mysterious illnesses.
But many specialists say its almost inevitable that DNA mapping eventually will be used for healthy young children too,maybe as an addition to traditional newborn screening for at least some tots. It takes a few drops of blood or a cheek swab. And while its still too costly for routine use,the price is dropping rapidly. Whole genome sequencing is expected to soon come down to $1,000,what it now costs for a more targeted exome sequencing that maps only certain genes and may be enough.
The NIH decided this was a window of opportunity to explore different ways this technology might be used. One of the four teams at Childrens Mercy Hospital in Kansas City will test rapid gene-mapping to speed diagnosis of babies in intensive care.
Another will look for narrow sets of genes important in childhood,such as those involved with immune disorders not detected by todays newborn screening or that alter how a child processes medication. Its not going to be some sort of fishing expedition throughout the genome, said Dr Robert Nussbaum of the University of California,San Francisco.
The two other projects at Brigham and Womens Hospital in Boston and the University of North Carolina,Chapel Hill will go a step further by enrolling healthy infants as they explore what kind of information parents want about their babies future.
We arent even sure that genome-scale sequencing in newborns is really a good idea, cautioned UNC lead researcher Dr Jonathan Berg in a recent Facebook chat to alert the community about the study. Rather than a one-time mapping,its possible that we will use targeted sequencing at certain times in a persons life,when that specific information will actually be medically useful.
For those pioneering babies whose DNA is being mapped already,researchers are trying to figure out what is legal,versus ethical,versus good medicine in revealing results,said Joe Vockley,Inova Translational Medicine Institutes chief science officer.
Mom and dad may be told something their child,once grown,wishes hadnt been revealed. Other findings may be withheld now that would be good to know years later,as new treatments are developed.
This is a living,breathing problem, Vockley said,not a static decision thats made,and it lasts for all time.