The genetics of the Olympics


The London 2012 Olympic Games might have come to an end but the Paralympic Games begins on 29 August, running through to 9 September, and throughout the whole event so far there has been a lot of talk about the role of genetics in elite sport. So, are Olympic athletes genetically better at sport? According to an article in Nature, "almost every male Olympic sprinter and power athlete ever tested carries the 577R allele, a variant of the gene ACTN3". This gene is expressed in skeletal muscle fibre and could have an effect on athletic performance – in total, more than 200 genes have been linked with athletic performance, including variants that improve endurance, or increase the numbers of red blood cells, so upping oxygen carrying capabilities in the blood.

This leads a number of questions:

  • Sports are already segregated according to sex – if there were genes that improved someone's chances in a particular sport, should they also be segregated genetically?
  • Should the athletes without the genetic mutations be allowed to have gene therapy to 'upgrade' themselves? Or should this so-called gene doping be outlawed, much as drug doping is (it is already outlawed in the US)? Widespread use of gene therapy in sport is unlikely to happen very soon.
  • Should the athletes with the genetic advantages carry 'handicaps' to bring them down to the level of the 'normal' athletes?
  • Should any athletes who have had gene therapy to cure disease be excluded?
  • And there is an ethical question too, raised at the Progress Educational Trust's Genetic Medalling event – could knowing about a gene for sporting prowess put too much pressure on individuals, especially as children? And on the flip side – would not having that gene make a child (or an adult) decide that it just wasn't worth trying?

As we learn more about genetics, we understand that in most cases a single mutation does not act alone. According to Ted Friedmann, chair of the genetics panel of the World Anti-Doping Agency: "Genes work in an enormously complicated set of interactions, and no gene works by itself. If you have the gene for speed or endurance, all the other genes you carry that [help] or work against that will affect how that gene expresses itself."

So whether athletes have no genetic mutations, one mutation, or a set of mutations, it still requires a combination of opportunity, environment, attitude, environment, determination and training, to make an Olympic athlete. It is still a lot of hard work.

This post first appeared on Genome Engineering - go to the blog for more posts.