Researchers have discovered 25 additional number variants (CNVs) - missing or duplicated stretches of DNA - that occur in some patients with autism. Even though the CNVs are rare, the researchers say that each has a strong effect in raising a person’s risk for autism.
“Many of these gene variants may serve as valuable predictive markers,” said the study’s corresponding author, Hakon Hakonarson, MD, PhD, director of the Center for Applied Genomics at The Children’s Hospital of Philadelphia. “If so, they may become part of a clinical test that will help evaluate whether a child has an autism spectrum disorder.”
These findings, said Hakonarson, could be incorporated into clinical tests for evaluating children for ASDs. “These high-impact variants could be most useful in advising parents who already have one child with an ASD,” said Hakonarson. “If a second child has delays in reaching developmental milestones, testing for these CNVs could help predict whether that child is also likely to develop an ASD.” He added that the newly identified variants would need to be added to the existing commercially available diagnostic array in current use.