Genetic testing in exercise and sport - have direct-to-consumer genetic tests come of age?

The general consensus amongst sport and exercise genetics researchers is that genetic tests based on current knowledge have little or no role to play in talent identification or the individualised prescription of training to maximise performance or minimise injury risk. Despite this, genetic tests related to sport and exercise are widely available on a commercial basis. This study assessed commercially-available genetic tests related to sport and exercise currently marketed via the internet. Twenty-two companies were identified as providing direct-to-consumer (DTC) genetic tests marketed in relation to human sport or exercise performance or injury. The most commonly-tested variant was the R577X SNP in the ACTN3 gene, tested by 85% of the 13 companies that appear to present information about their genetic tests on websites - which corresponds with our assessment that ACTN3 R577X is currently the polymorphism with the strongest scientific evidence in support of an association with sport and exercise phenotypes. 54% of companies that present information about their genetic tests used panels of 2-21 variants, including several with very limited supporting scientific evidence. 46% of companies tested just a single variant, with very low ability to explain complex sport and exercise phenotypes. It is particularly disappointing that 41% of companies offering DTC genetic tests related to exercise and sport did not appear to state publicly the genetic variants they assess, making scrutiny by academic scholars and consumers impossible. Companies offering DTC genetic tests related to sport and exercise should ensure that they are responsible in their activities.

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