Monday, May 9, 2016

Newborn genome sequencing

But families could learn much more. While the cost of testing an entire human genome is plummeting, the health data available from that testing continues to increase. A baby’s genome, if sequenced, might reveal some of the approximately 8,000 genetic disorders that are otherwise very hard to diagnose—disorders that, collectively, can account for as much as 35% of deaths during the first year of life. Wouldn’t combining genome sequencing with that prick on the heel save more lives?

Probably. But genetic screening—at any age—can also have a less positive side, uncovering genetic clues that lead to stress but few medical solutions. In fact, some people prefer not to know what their genes might predict. To untangle that knot, the National Institutes of Health started the Newborn Sequencing in Genomic Medicine and Public Health program. Known as NSIGHT, it is funding four pilot projects that seek answers to ethical, legal and social questions related to the genes of newborns.

“We need to ask if it provides clinical utility. Does it help the doctor treat the baby? Does the baby have better outcomes as a result?”

In some instances, the answer is yes. One of the four NSIGHT projects is studying babies in the neonatal intensive care units (NICUs) at Children’s Mercy Hospital in Kansas City and Rady Children’s Hospital–San Diego. Led by geneticist Stephen Kingsmore, clinicians developed techniques to rapidly test for 4,500 known diseases that might affect the health of the baby and have results returned in as little as 26 hours—a technological tour de force. Preliminary results showed 20 diagnoses in the 35 infants who underwent sequencing, and 13 of those led to treatments—which, Kingsmore says, is “unprecedented in the NICU.” He told of one infant who was in danger of dying from acute liver failure from an unknown cause. The sequencing revealed a treatable blood disease. The baby became symptom-free within seven days of treatment and is now healthy.

But in many other cases, learning genomic secrets may not offer any material benefit. Most of the thousands of rare genetic diseases are poorly understood and can’t currently be treated. Some, such as Huntington’s disease, will not strike for decades. Knowledge of such a condition may not bring any health benefits to the child and, instead, may hang over their childhood, causing harm and stress to both family and child. So another NSIGHT project at Brigham and Women’s Hospital in Boston and Boston Children’s Hospital, called the BabySeqproject, is enrolling healthy and sick newborns and their parents. The study will follow families—some of whom received a full genetic breakdown for their newborns, some of whom didn’t—and try to learn more about how the test affects the family in the baby’s first year of life...

Genetic data is not always straightforward: Many genes don’t predict a disease with certainty; they only increase the likelihood of developing it...

A lifetime with that knowledge might result in decades of worry and screening that, ultimately, do more harm than good. Full genome sequencing of infants would require intensive one-on-one counseling with the parents, according to Natasha Bonhomme, an executive at Genetic Alliance, a nonprofit organization: “And when you have a new baby, there is already so much going on that it’s a difficult time to process complex information.”

Genetic screening of newborns also raises questions about what rights patients have regarding their own genetic data—and especially, in light of the potential trauma of receiving murky genetic information, their right not to know about it. “One of the most important policy issues will be what options parents have for not receiving certain kinds of results,” says Catherine Wicklund, a researcher at the Center for Genetic Medicine at Northwestern University.  In a 2015 survey of genetics professionals, she found—amid much disagreement about particulars—broad consensus that genome sequencing of newborns should not be mandatory. It should involve an extensive consent process that allows parents to choose which results they want to learn and when; and it should require pre- and post-test genetic counseling for parents.

So looking into the genes of newborns offers something of a Faustian bargain. On one hand, the child and parents can gain a storehouse of important knowledge and the power to act on it. On the other, they risk needless confusion and worry. “That’s why we’re doing these NSIGHT studies,” explains Anastasia Wise, a program director with the National Human Genome Research Institute, another agency funding the study. For the moment, that means taking all of the clinical and psychological repercussions under investigation and proceeding with baby steps.

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