Thursday Nov 14, 2024
Wednesday, 2 March 2016 00:00 - - {{hitsCtrl.values.hits}}
On 5 November 2015, a quiet milestone was achieved in medical history. One-year-old Layla Richards was injected with TALENs (Transcription Activator-Like Effector Nucleases). These molecular scissors were used to edit DNA inside Layla’s body. Layla had Acute Lymphoblastic Leukaemia (ALL) with a poor prognosis. Now with this technique immune cells hunted down these leukaemia cells and destroyed them at the core of their structure. Welcome to the future.
This February “gene editing” research was given the go ahead on human embryos by the UK Human Fertilisation and Embryology Authority (HFEA). The landmark research takes place at the Francis Crick Institute in London. Surprisingly the use of CRISPR/CAS9, TALENs and ZFNs is not new and has been in the scientific realm for many years. The principle is to identify “spaces” in the DNA and these areas are cut by a protein and RNA (ribonucleic acids). The technology has been applied in agriculture and various animal experiments in mice and rats.
Potential future applications?
Gene silencing/gene editing in medicine: We all inherit the good and the bad, and a lot of us do inherit bad genes. Usually baldness, colour blindness and other minor manifestation will not have a major impact on our wellbeing. More serious inherited or environmental mutations such as a cancer or an inherited disease could be very detrimental to our health.
The case of Layla might be the first of its kind but it definitely will not be the last. Diseases that have been clearly linked to specific mutations in DNA will be the primary area of benefit in the next 10 years where gene editing will come to play. Clinicians and patients would now be able to lean on what could possibly be absolute treatments. Imagine being able to suppress early onset diabetes using this technique and the follow on reduction in disease burden to healthcare and government?
What about combating infectious diseases? Human Immunodeficiency Virus (HIV) infections now possibly have a long term solution. Recent research has shown that by editing the CCR5 genes in humans it is now impossible for the most common variants of HIV to cross over (Eisenstein, 2015). It’s quite possible that even multi-resistance seen in infections today might see resolution with these type of cutting edge techniques.
Commercial applications – agriculture/animal husbandry: The future of GMO (genetically modified organisms) is already here and these techniques will further push the boundaries of commercial food production. On the upside the modifications will be more precise and less hazardous. Yet in techniques such as these how it is used needs to be regulated. Creating crops resistant to weed killer could be seen as detrimental compared to edited genes that could possibly make a crop or farm animal more immune to external infections.
Public health: As new techniques emerge for monitoring disease propagation and controlling epidemics or endemics in public health, gene editing seems a viable tool to resolve immediate threats. Research has been done internationally on disrupting the TEP1 gene (Ainsworth, 2015), which make the mosquito susceptible to the malarial parasite hence reducing transmission by eliminating the host. Its research like that which could control outbreak of disease, reduce disease burden and create preventive steps to exposure. It’s not all roses as harnessing the power of such flexible technology can be a challenge as outcomes can also bring about other challenges.
What is the financial impact?
These “kits” now cost anywhere from under $ 1,000 and go up to $ 2,000 approximately. The prices do keep coming down. Of course all of this is research use and lab facilities are needed to bring out the potential commercial applications so they can be applied. Yet in the big scheme of things it does not cost a lot.
Where are we now?
On 16 February two news articles were released both showing various forms of this technology being applied. One was in the treatment of blood cancers where the first trials of modified T immune cells had seen positive results. The other was how healthcare authorities plan to use a genetically modified mosquito (product by Oxitec in UK), so it will not have the ability to carry the Zika virus.
As one may surmise the technology of gene editing/gene silencing is no more a novelty but now considered a revolutionary method of dealing with today’s disease and public health problems. Apart from that the commercial aspects would bring immense value to both agricultural and livestock products. Of course as with any new technology regulation without inhibiting its potential and monitoring outcomes of applications will be key to its success.
Footnotes – works cited
Ainsworth, C. (2015, December 3). Agriculture: A new breed of edits. Nature, S15-S16.
Eisenstein, M. (2015, December 03). Disease: Closing the door on HIV. Nature, S8,S9.