By George Aitch
We have previously had much to say on the subject of gene editing. This year the CRISPR method of genetic engineering has been used to alter human embryos to remove a gene which increases the risk of heart disease.
Previous trials, some awaiting conclusion, have attempted to eliminate blindness or lung cancer in living subjects. This study, carried out by a US-South Korean group of scientists, aimed to remove a single point mutation (one faulty gene) which is known to cause a condition called ‘hypertrophic cardiomyopathy’ or HCM. HCM leads to the muscle of the heart becoming thick and stiff, preventing it from pumping effectively. This disease has made headlines before, being famous for causing very sudden deaths, usually in young athletes in whom it was undiagnosed. Such a condition is obviously one which we would like to prevent, especially given that there is no known cure and it can be passed onto children of those who might unknowingly suffer from it.
The trial’s scientists altered the genomes of X zygotes known to be at risk of the disease, leading to 72% being free from the mutation (MYBPC3) which led to HCM. Five days later, after the results were confirmed, the study was terminated. This breakthrough is exciting not only because it would remove the risk of HCM in an individual, but also the individual’s offspring – potentially leading to a family free entirely from HCM provided that the single point mutation has been corrected. If this were employed in the future, then embryos could be selected which have been repaired as to not carry the harmful MYBPC3 mutation.
But this taking of evolution into our own hands has caused consternation to some. As with most cutting-edge research, there are some concerns which need to be addressed. First, from a practical standpoint, the technique used has some drawbacks. The problem with repairing genes in this way is that it may potentially introduce mutations into other points of the genome – hardly a desirable outcome when mutations are what we’re trying to prevent. Until this method is safe, we probably aren’t going to see it rolled out across the country’s IVF clinics.
Ethical questions have also been raised. The CRISPR gene editing process gives us the ability to select embryos (and future humans) for their desirable or undesirable characteristics. The potential worry here is that those characteristics might not be diseases but features such as sex, or hair and skin colour. This has been the issue raised in science fiction, as with Gattaca or Brave New World, where society becomes stratified by characteristics ordered and selected from birth.
This holds up a mirror to our own current social mobility, whereby a citizen’s position in society is often preordained by the standing or wealth of their family (something which they have already inherited from their parents). This is precisely what we should be moving away from; the labelling of anthropological features harks back to pseudoscience of the nineteenth century; racial biology and phrenology. Definitely a step back. At present, the science is struggling to keep pace with the speculation and morality, however these are issues we are going to have to discuss and address if we want to keep moving forward. Talk of ‘designer babies’ may seem old hat, but their existence is only a heartbeat away.
At Trusted Medicine we are improving Public Health through education. We love what we do, but we need your help. Please share our work, help us reach more people.
Any opinions above are the author’s alone and may not represent those of his/her affiliations. Any comment is based on the best available evidence at the time of writing. All data is based on externally validated studies unless expressed otherwise. Novel data is representative of the sample surveyed. An online recommendation is no substitute for seeing your own doctor and should not be taken as medical advice. Article proofed and edited for publication by Dr. BM Janaway.
Sources and Further Reading
- Ma H, Marti-Gutierrez N, Park S, Wu J, Lee Y, Suzuki K, Koski A, Ji D, Hayama T Ahmed R, Darby H, Van Dyken C, Li Y, Kang E, Park AR, Kim D, Kim S, Gong J, Gu Y, Xu X, Battaglia D, Krieg SA, Lee DM, Wu DH, Wolf DP, Heitner SB, Belmonte JCI, Amato P, Kim J, Kaul S, Mitalipov S. Correction of a pathogenic gene mutation in human embryos. 2017. Nature. Available here: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature23305.html?foxtrotcallback=true
- Photo sourced from Pixabay