Editing of Human Embryo What is CRISPR? Clustered regularly-interspaced short palindromic repeats (abbreviated as CRISPR , pronounced crisper are segments of prokaryotic DNA containing short repetitions of base sequences. Each repetition is followed by short segments of " spacer DNA " from previous exposures to a bacterial virus or plasmid . How t o U se? By Editing Genome CRISPRs have been used to cut five to 62 genes at once: pig cells have been engineered to inactivate all 62 Porcine Endogenous Retrovirus in the pig genome, which eliminated infection from the pig to human cells in culture. CRISPR's low cost compared to alternatives is widely seen as revolutionary. Selective engineered redirection of the CRISPR/Cas system was first demonstrated in 2012 in: · Immunization of industrially important bacteria, including some used in food production and large-scale ferment