Scientists Expand CRISPR-Cas9 Genetic Inheritance Control in Mammals

Biologists achieve gene conversion in male mice, broadening potential for human disease research and environmental applications. Nearly three years ago University of California San Diego researchers announced the world's first CRISPR-Cas9 genetic editing-based approach to controlling inheritance in mammals. The 2019 achievement described research led by then-UC San Diego graduate student Hannah Grunwald and Associate Professor Kimberly Cooper, who employed "active genetics" editing, a technology developed at UC San Diego, to influence the inheritance of genes in mice. This gives biologists the ability to control which copy of a gene is inherited from one generation to another with potential for a variety of biomedical and environmental applications. The research succeeded in female mice but not in males, presumably due to differences in the timing of key events in females and males during the reproductive cell division process known as meiosis. Led by graduate student Alexander Weitzel, Grunwald, Cooper and their colleagues have now succeeded in developing CRISPR-Cas9 inheritance control in male mice by shifting the gene editing window to more closely match the timing of meiosis in both sexes. Their results were published December 23, 2021 in the journal PLOS Biology.