The researchers taking part in the study say it’s too soon to recommend such wide genetic testing for the general public. But they say their findings suggest that in some cases, and for some people, it may be worth doing.
“This is a kind of glass half full, glass half empty situation. On one hand, you are identifying those babies as at-risk and we know many of them will never develop the disease in question,” said Dr. Robert Green, a professor of medicine at Harvard Medical School and Brigham and Women’s Hospital, who worked on the study.
“On the other side, you're identifying disease risks which are actually actionable, you can do something about. So these babies can be monitored … and you can actually look for these conditions and try to prevent them or mitigate them,” Green told NBC News.
Green and colleagues are testing newborns for about 5,000 different genetic variations linked with disease as part of a larger project called BabySeq. Their report on what they found in 159 of those babies is published in the American Journal of Human Genetics.
Just over 9 percent of the babies had genetic sequences that could put them at risk of diseases that might appear during childhood, such as hearing loss or heart defects. One had immediate symptoms linked with the genetic sequence: Cora Stetson, now 2, has a genetic tendency to be deficient in biotin, an important B vitamin.
Other tests showed that Cora did indeed have low levels of biotin, something easily corrected with a daily supplement. “So we give her a supplement every night with dinner. We put it in yogurt,” Lauren Stetson, her mother, who lives outside Boston, told NBC News.
Without biotin, Cora’s development could have been affected. “She could have had just decreased vision, maybe trouble hearing, cognitive problems,” Stetson said. “She may just have struggled in school and we'd may just have said, ‘oh well, she just has a hard time learning’ or ‘she just needs glasses’ or any of those things,” she added.
“But is so easily fixed for us now that we know that's exactly what's going on.”
Green counts Cora as a success. “So, I'd like to think when this baby's in college we may have contributed to her good grades,” he said.
Most of the other cases, however, were fuzzier. Only a handful of parents signed up for the testing, and they did not always get clear answers to questions. A girl born with respiratory distress had a genetic variant linked to Lynch syndrome, which puts people at high risk of various cancers throughout life. A boy born with a narrowed heart artery had a genetic defect linked with a red blood cell disorder. They were among 32 babies in the NICU who were tested as part of the project.
“One of the things they did not see in this paper was they did not get an unequivocal answer for those families. There were families who wanted testing to answer the question of why their baby was sick, and some of those families did not get answers,” said Heather Zierhut, associate director of the Genetic Counseling Program at the University of Minnesota, who was not involved in the study.
That tells Dr. Wendy Chung that this kind of testing is not ready for wider use.
“Most (parents) probably got knowledge that wasn’t useful for a newborn baby,” Chung, an expert in pediatric genetics at Columbia University, told NBC News. “It’s not what we need to be doing right now. It’s not what parents want.”
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