Scientists have been exploring the "hows" and "what ifs" of applying sequencing to newborn screening. However, two new National Institutes of Health-sponsored studies presented at the American Society of Human Genetics annual meeting (Vancouver, Oct. 18-22, 2016) are dashing hopes that every newborn will have their genome sequenced any time soon. The NBSeq project found that whole-exome sequencing (WES) does not have "acceptable" accuracy to replace traditional newborn screening, while, a second project, BabySeq, found that parents are not that interested in having their newborns sequenced. Exome Sequencing Not Accurate Enough for Newborn Screening The NBSeq project found that WES of newborn dried blood spots misses 25 percent of metabolic disorders found by traditional newborn screening with tandem mass spectrometry (MS/MS). The authors say these findings indicate limits to WES both in newborn screening and diagnostic testing. MS/MS detects many metabolic disorders with excellent sensitivity, but often does not identify the precise disorder, experts say. Given newborn screening is done at the population-level it must scale and have greater than 99 percent specificity. By contrast, sequencing performed on patients suspected of genetic diseases is cumbersome, requiring manual review from experts, and still has a diagnostic yield between 25 percent and […]