Finally, a doctor might request a genetic test for a child who may not be developing at the typical rate. Unlike older patients, babies show all the same symptoms whether they have a severe genetic condition or are just colicky, so it’s almost impossible for physicians to tell if something is wrong based on feeding and sleeping habits. But developmental milestones are a better indicator; if a baby doesn’t roll over by the time he is six months old or walk by 18 months, there might be a genetic reason why. “If parents have a child in front of them with an issue that doesn’t fit a particular syndrome, they might want to know the specific disease and its mutations,” Klugman, the reproductive genetics expert, says. “That way the doctors could tailor the disease management and the parents could plan for future siblings. And whole exome sequencing may help elucidate the issue,” When it comes to treatment, the earlier the intervention, the more effective it can be, Mittelman adds.