Ultrasound is often used for prenatal screening. It's just one of several prenatal screenings available to pregnant women. iStockphoto hide caption

itoggle caption iStockphoto

The CRISPR enzyme (green and red) binds to a stretch of double-stranded DNA (purple and red), preparing to snip out the faulty part. Illustration courtesy of Jennifer Doudna/UC Berkeley hide caption

itoggle caption Illustration courtesy of Jennifer Doudna/UC Berkeley

Vera Wojtesta was one of 300 babies flagged by New York's newborn screening program as at risk of having life-threatening Krabbe disease. Ben Shutts/Courtesy of the Wojtesta family hide caption

itoggle caption Ben Shutts/Courtesy of the Wojtesta family

Slides containing DNA sit in a bay waiting to be analyzed by a genome sequencing machine. David Paul Morris/Bloomberg via Getty Images hide caption

itoggle caption David Paul Morris/Bloomberg via Getty Images