Also known as is CRISPR-Cas9, the acronym for ”Clustered Regularly Interspaced Short Palindromic Repeats” and the active enzyme Cas9. It is a sequence of genes that are a bacterial defense system, which are used in the gene modification technology. With CRISPR, “researchers can permanently modify genes in living cells and organisms and, in the future, may make it possible to correct mutations at precise locations in the human genome in order to treat genetic causes of disease.” CRISPRs act like an immune system because they defend against potential dangers.
CRISPR can Turn off a gene with an enzyme called Cas9 which can cut part of a targeted DNA sequence. It can also activate a gene, which allows scientists to study a cell’s function. “Research also suggests that CRISPR-Cas9 can be used to target and modify “typos” in the three-billion-letter sequence of the human genome in an effort to treat genetic disease.” It also helps with research because it allows animal models to be made which can be subjects for research on cancer.
Before CRISPR, other tools to modify genes existed, but something that makes CRISPR unique is that it can target multiple genes simultaneously. It is also more accurate than other genome editing tools. One study found a 78% accuracy in single-celled mouse embryos and greater than 70% success in zebrafish, compared to other genetic modification tools ZFN and TALEN with ranges of 1-50% accuracy rates.
There have been “Recent improvements to the CRISPR system for reducing off-target mutations.” Off-targeted mutations are unexpected mutations not in the desired DNA sequence. They are an important consideration when designing a genome editing tool. One method involves the use of two proteins each at the end of the sequence to limit the range of mutations. It is designed in such a way that there should only be single nicks in off-targeted mutations with minimal consequences.
There is an ethical concern regarding how far scientific advancement of CRISPR can be taken. Is it wrong to change a person’s genetic makeup? Are we dehumanizing them, or are we improving their lives?Tags: biology crispr genome editing science