Around 10% of defects observed in babies born with congenital heart disease are caused by genetic mutations absent in both parents, new research shows.
While genetic factors do indeed contribute to congenital heart disease, that many affected children have healthy parents and siblings suggests such mutations arise spontaneously.
Using next-generation sequencing, Yale School of Medicine’s Richard Lifton and his colleagues compared the exomes of children with an without congenital heart disease and their parents, finding that such de novo mutations explained around 10% of severe cases. The researchers also found that mutations in several hundred different genes contribute to this trait in different patients, concentrated in a pathway that regulates key developmental genes. They published their findings in Nature this week.
“The mutations in patients with congenital heart disease were found much more frequently in genes that are highly expressed in the developing heart,” Christine Seidman, study co-author and professor of genetics at Harvard Medical School, said in a Howard Hughes Medical Institute statement.
Writing in Nature, the researchers noted having found “a marked excess of de novo mutations in genes involved in the production, removal, or reading of histone 3 lysine 4 (H3K4) methylation, or ubiquitination of H2BK120, which is required for H3K4 methylation”—genes that also appear to play a major role in autism, Lifton said.
Seidman added that understanding such variation could eventually help doctors improve patient outcomes. “After we repair the hearts of these children, some children do great and some do poorly,” she said.
“De novo mutations in histone-modifying genes in congenital heart disease” was published in Nature May 12.