The biotech firm Editas Medicine says that humans who have had their DNA genetically modified could exist within the next two years. Nonsense. Even in America, where there’s no popular resistance to GM foods, such a procedure might take years to gain a licence. In the EU, where even GM cereals are not yet allowed human GM might never be (as long as the EU exists, that is!).
Editas Medicine thinks that the poignant case of someone born with Leber Congenital Amaurosis (LCA) — which causes severe vision loss at birth — will suffice to obtain fast-track approval. They can correct the condition, they say, by gene editing. This involves the excision of a gene with a harmful variation and replacing it with what could be called a ‘standard’ gene. This — the procedure and the desired result — may very well be possible, but it still might not be allowed.
While GM cereals are innocent enough, GM human genes are certainly not. The reason is that the DNA of soya or wheat or maize contain a huge number of genes already — far more than humans’ 23,000 — and it’s only a matter of adding one extra gene with the required trait (for example, resistance to a particular virus). The added gene simply adds to the ‘repertoire’ of the existing DNA.
In humans every gene is multi-purpose. It takes part in many different functions of the body. At any one time all active genes are associating with other genes to do what the body needs. If you alter one variation of a gene it might have several different effects and, paradoxically, some gene variations which are harmful in causing one condition might be beneficial to another. Sickle cell anaemia, for example, is not a pleasant disease to have but sufferers are also protected from malaria, so there’s a net gain if you live in a malaria-infested region of the world.
So proving that gene editing in a case of LCA might be successful in giving the child full vision it may have adverse effects elsewhere. Some LCA patients also experience central nervous system conditions, such as epilepsy, developmental delays and motor skill impairment and these may not be apparent for years. Will GM treatment for vision also correct these other handicaps? — or could they be made worse? — or could there be additional adverse effects?
On the face of it, Editas Medicine don’t have a chance of pulling this off — legally — within two years. Or is it going public and this is publicity in order to attract share-buyers?