As the first of our 2019 Café Scientifique talks, Dr Matthew Wheeler delivered a lecture about CRISPR to students from Years 11 to Upper Sixth. This is a relatively new technology that allows targeted alteration of DNA.
The technology has been developed from short sequences found in bacterial DNA. These short sequences are used to find matching sequences on the target DNA. Once found, the system uses an enzyme to cut out the sequence. The system is also capable of inserting a section into the DNA at this point.
Possible applications for the technology include: modifying crops to resist disease; creating animals that produce more meat; eradicating disease-carrying insects and treating or curing human genetic disorders.
Sections of our DNA, known as genes, are responsible for our physical traits such as eye colour, hair colour, the presence of a widow’s peak and whether our earlobes are attached or not. Genes are also responsible for genetic disorders such as cystic fibrosis and muscular dystrophy, both of which have high fatality rates. CRISPR has the potential to enable us to modify these genes and cure these diseases. So should we just do it? What are the possible side effects? These are some of the questions scientists are debating all over the world.
In China, one scientist has already performed human trials using this technology. He has created twins who are resistant to the HIV virus. Last September a clinical trial was launched to use CRISPR in the treatment of β-thalassemia, a disease affecting red blood cells. Treatment of retinal degenerative blindness using CRISPR has also gained FDA approval in America. Although the technology is target specific, it is possible that it could target a similar sequence in a different part of the DNA. The effects of these ‘off target’ alterations are almost impossible to quantify, so this is one of the main issues with CRISPR.
Overall, one point rang through clearly, CRISPR is an exciting technology with a wide range of possible applications. But, in a society where people strive to be ‘perfect’, who decides where the ethical boundaries lie with genetic modification? This was fascinating food for thought for Woldingham's scientists of tomorrow.
Miss Ceara Kelly, Teacher of Chemistry