It’s about time I did a post on CRISPR-Cas9! As always, words in pink will be added to the glossary
CRISPR-Cas9 is an up-and-coming method for gene modification, which has taken the scientific world by storm.
What is CRISPR?
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) are repetitive sections of DNA, associated with the Cas9 endonuclease. It is commonly found as part of the bacterial immune system.
What does it do?
The CRISPR-Cas9 protein uses specific RNA guides to target and cleave very specific DNA. This means that CRISPR-Cas9 can be used for cutting highly targeted sites along the genome. The RNA guides the specificity, and can be artificially edited in vitro. CRISPR can knockout a gene of interest, and can also be used to cut out a gene, and replace it with a new one. In short, it can be used to edit a genome precisely, and this has had a massive impact on the studies of genetics, development, and improving human health.
Good or bad?
Many people have hailed CRISPR as the beginning of a new era of genomic engineering, with potentially vast consequences for human health and disease treatment. The possibilities that come with being able to accurately edit single regions of the genome are endless- some suggestions include:
- Modifying crop plants to be more resistant to diseases
- Inactivating retroviruses (such as HIV, CMV and VZV) that have integrated into the genome
- Mutate genes that cause disease in humans, and removing genes that cause cancer proliferation in tumours
However, this is still a new technology, and concerns have been raised over potential ethical dilemmas that may arise from CRISPR-Cas9. Many people are not happy with the idea of being able to edit the human genome, potentially leading to ‘designer babies’ and unnecessary changes to the human germline. Although CRISPR-Cas9 appears to be very accurate, it could cause a lot of damage if mis-directed to the wrong area of the genome. Nevertheless, many trials on somatic cells are underway, to see if treatments for genetic diseases could be cured by this technology.
A group of scientists have been given permission to carry out tests on human cells for use in therapeutic treatment of lung cancer. It will be exciting to see how this treatment works, and whether CRISPR-Cas9 lives up to its expectations.