Full-Genome Tests for Your Kids? For You?
If you could get a printout of your entire genome for $1000, would you? What about one for your child?
Human genetics expert Ricki Lewis, PhD and author of several genetics textbooks and thousands of scientific articles, says she’ll pass. In her view of whole genome sequencing (WGS), “the state of the science provides both too much and too little information.” It reveals too much information, she explains, in that many segments of the sequence are useless or uninterpretable, or code for late-onset disease for which there is no known cure or treatment. At the same time, Lewis says, that the sequence reveals too little information – and always will – because “we need to know more than a string of DNA letters or a list of gene variants. We need to know how our genes interact.”
In a recent series in Time magazine on whole genome sequencing for children, reporter Bonnie Rochman explores these concerns by profiling families, doctors, and genetic testing companies. She seems particularly struck by how Americans’ need-to-know ethos can skew their understanding of the risks and benefits of whole genome sequencing.
In some cases, of course, the benefits of having a child’s genome sequenced are clear. As Rochman notes, “WGS can provide early warning about some of the deadliest and most debilitating diseases. Those warnings, in turn, can enable timely treatment or at least allow people to make plans about long-term care” when treatment isn’t possible.
So for a child like Juliet Belcher, who has significant physical and cognitive impairments with no explanation as to why, WGS might provide critical information about a diagnosis and a treatment plan. Juliet’s parents, who decided that for them the benefits outweighed the risks, have yet to hear back about her genome.
Another mother whose child suffers from impaired physical and cognitive development that doctors have been unable to diagnose made the same decision. Laurie Hunter has received the results of her daughter Amanda’s genome test – and they were damaging enough that she has questioned why she participated. “Sometimes,” she says, “what you don’t know is easier.” What made the results so upsetting was that they uncovered nothing about Amanda’s problems. The only abnormality doctors could identify was a genetic deletion that could code for rare, fast-growing tumors, but that unfortunately is located in a part of the human genome about which medical professionals still know very little. The discovery about the heightened risk of future cancer was something with which the Hunter family felt unable to cope. “I feel completely overwhelmed with information. Now it just feels like a waiting game,” Laurie explained.
The Hunters’ experience seems to affirm what skeptics like Lewis believe: that for healthy people – children or adults – the risks of uncertain or non-actionable results make WGS unpalatable. But it appears that many young families don’t agree. Rochman reports that one study has enrolled 2500 families, many with healthy newborns, who have agreed to have their babies’ genomes sequenced. These children, who didn’t themselves choose to know about all their genetic information, may have to continue worrying about it long after their parents are gone.
Rochman also touches on the companies that offer direct-to-consumer gene tests, and the plans by some to move into whole genome sequencing. Anne Wojcicki, founder and CEO of 23andMe, told Rochman that as a parent, “the most responsible thing I can do is get as much information about my children as possible,” with or without the guidance of a doctor. But other leaders in the industry disagree. Maryland-based GeneDx will only provide genetic testing at the request of a doctor; San Diego-based Illumina, which is already offering WGS directly to consumers, refuses to sequence kids who aren’t sick. “We do it on children when we’re trying to save their lives,” CEO Jay Flatley told Rochman. “We don’t believe parents have a legal or ethical right to do this [just for fun].”
And then there are the social and economic drawbacks to widespread genome sequencing. Rochman raises some of these concerns in the final article in her series, under the title “Why Cheaper Genetic Testing Could Cost Us a Fortune.” As the whole-genome tests become cheaper and more widely available, what happens when parents try to interpret the inherently uncertain results? Will their anxiety wind up dramatically increasing the number of unnecessary extra medical procedures performed, and make insurance costs skyrocket? The need-to-know frenzy that individual parents feel could wind up having a seriously negative effect on the entire health care system.