CRISPR-Cas9 technology holds promise for treating inherited disorders, but scientists are also exploring its utility for excising integrated viruses. Early reports have demonstrated that CRISPR effectively excises integrated human immunodeficiency virus type 1 (HIV) from cells.1,2 For Michele Lai from the University of Pisa, these studies raised an important question: what happens to the excised DNA?
He set out to answer this question, and recently published in the Journal of Virology that some of the excised viral DNA molecules form stable DNA circles that can reintegrate into the genome.3 This phenomenon may pose a challenge to those working on CRISPR-based HIV treatments.
Even if CRISPR works in 100 percent of T cells, you would still have a good number of cells where the [plasmids] can start the infection over.
—Mauro Pistello, University of Pisa
“In this context of genomic instability, the cell doesn't understand what is the DNA of the cell ...
