Since its invention, CRISPR has let scientists introduce DNA changes at specific locations in a genome. Often these precise changes are made one at a time.
Perhaps not for much longer. A team at Harvard University says it has used the technique to make 13,200 genetic alterations to a single cell, a record for the gene-editing technology.
The group, led by gene technologist George Church, wants to rewrite genomes at a far larger scale than has currently been possible, something it says could ultimately lead to the “radical redesign” of species—even humans.
Large-scale gene editing of this sort has been tried before. In 2017, an Australian team led by Paul Thomas peppered the Y chromosome of mice with edits and succeeded in blasting it out of existence. That strategy is being eyed as a potential treatment for Down syndrome, a genetic disorder caused by an extra chromosome.
To set the new gene-editing record, team members Oscar Castanon and Cory Smith aimed CRISPR at a type of DNA sequence called a LINE-1, a mysterious repetitive element found littered across the human genome. These genetic elements, which are able to copy themselves, are estimated to account for about 17% of our genome.