A DNA “mimic” to repair genes

A peptide nucleic acid (PNA) that mimics DNA holds the promise of repairing defective genes, according to Yale radiologists and geneticists.

PNA, which replaces DNA’s phosphodiester backbone with a polyamide one, creates a strong bond with DNA, said Peter M. Glazer, M.D., Ph.D., professor and chair of the Department of Therapeutic Radiology. “If you can bind something to the gene, maybe you can use that to change the gene,” he said. “If you change the gene to a new sequence it is permanently fixed.”

In a study published in December in the Proceedings of the National Academy of Sciences, Glazer, the senior author, described the use of PNA to introduce a specific DNA sequence into a target gene in extracts of human cervical cancer cells. The new DNA sequence corrected a mutation in the target, the authors reported.

PNA, they concluded, could serve as a tool both for research and for repairing genes implicated in hereditary diseases such as sickle cell anemia and cystic fibrosis.