Gene Therapy and Doping

Gene therapy does hold a lot of potential for doping. Unfortunately it could be very hard to detect, let alone the possible adverse effects on the athlete. There are even a few areas of paediatrics where gene therapy has already been used, but by and large it is still in the "potential" basket.

In short, genes are the "messages" contained in your chromosomes/DNA which tell individual cells which proteins to make and which regulate the use of these proteins. Proteins pretty much make up all your enzymes, and the other parts of your cells which "do stuff". When people have a genetic disorder, which includes things like Cystic Fibrosis, Muscular Dystrophy, and inumerable others, a faulty gene causes them to have either too little or too much of some protein or other which lead to a the cell to not function correctly and much further down the line, the organism as a whole to manifest some problem. This can be so minor as to be unnoticable or so profound that it is incompatible with life. (Down syndrome is also a genetic disorder, but involves having an extra chromosome no.21 which has thousands of genes, leading to lots of potential problems).

The aim of gene therapy is to alter the expression of a single gene, hoping to change the end effect on the person so as to alleviate the problem produced by the faulty gene. The problem is that all of our genes are regulated by our DNA in complex ways that are kind of like using the dimmer switch on a light- relatively few are of the simple on-off variety- and the precise "intensity" of the gene expression is critically important to our function. These genes are much harder to do gene thearpy on than the on-off ones. Why? read on.

Gene therapy involves trying to insert a working copy of the faulty gene into your DNA using a carrier, which is usually a virus or bacteria which has the ability to incorporate into your DNA (or genome). At present, this is no precise science, rather more like throwing anough sh*t and hoping that some will stick. The best success rate the I have read about recently is a 1% take- so you have 1% of the normal gene function. In a condition where you have no functioning gene at all, this can be the diffenence between life and death (I can think of an immune deficiency where this is the case). In other situations, it may be a total waste of time that make no noticable difference. Other techniques involve trying to block a gene that is producing too much of a harmful protein- I am not aware of any of these that are successful. Back to our cow- if we were trying to get really big muscles, we could try to block the myostatin gene.

The problems of gene therapy can involve the carrier virus/bacteria being harmful- some kids have got leukaemia which is definitely related to their gene therapy; the gene alteration having unpredicted consequences- hypothetically, making your muscles bigger might occur so quickly that tendon ruptures occur, as seen in steroid use; or other ways that we don't yet know about.

That all said, you can imagine that there is plenty of energy being put into this field, and like EPO (the magnitude of sporting use is miniscule compared to its valid medical uses), and if sporting spinoffs can be found they will be.

Hope that is of some interest.