A mutation affecting factors that influence gene activity - the epigenome - could induce, researchers have found, an inherited form of mental retardation in boys.
The findings may help scientists further understand why X-linked disorders cause cognitive impairment and develop new therapies to treat or prevent them.
Hank Qi and his collaborators, Madathia Sarkissian and Thomas Roberts at Dana-Farber Cancer Institute, tested the normal enzyme function of histone demethylase in zebrafish, a popular model for genetic function.
The team found a dramatic impact on craniofacial development and the fish without the enzyme developed virtually no jawbone.
"These studies suggest that the imbalance of histone methylation dynamics plays a critical role in mental retardation. You can imagine a therapeutic approach to enhance the compromised enzymatic activity or to restore the downstream function," says Yang Shi, also a professor of pathology at Harvard Medical School.
The study is published online July 11 in the journal Nature.