Question

In a CRISPR-Cas9 experiment, how many sites matching the cRNA can the protein cut if multiple sites are found in the cell?

a. One site per experiment
b. Depends on the quantity of Cas9 protein
c. Unlimited cuts per Cas9-sgRNA complex
d. Only one chromosome can be cut

Answer 1

In CRISPR-Cas9 experiments, Cas9 can make unlimited cuts at sites matching the sgRNA if multiple sites are available and the system is adequately supplied with Cas9 protein and sgRNA complexes, allowing precision gene editing.

Step-by-step explanation:

In a CRISPR-Cas9 experiment, the number of sites matching the cRNA (now commonly referred to as sgRNA or single guide RNA) that the Cas9 protein can cut is theoretically unlimited as long as the sites are present within the genome and there is sufficient Cas9 protein and sgRNA complexes available in the system. This means the CRISPR-Cas9 system has the potential to target and cut multiple sites concurrently within the cellular environment. Moreover, this system allows for precision gene editing, enabling the alteration of the genomic DNA at specific, exact sites with high efficiency.

CRISPR technology has been revolutionary in enabling scientists to conduct genetic engineering with greater ease and precision. However, it's also worth noting that for applications in living organisms, the immune recognition of the Cas9 protein can form a barrier to the successful application of CRISPR technologies.