Jury is still out on value of genetic biomarkers

This week's newsletter features a number of stories about gene-based biomarkers, and there has been an explosion in these since the sequencing of the human genome over a decade ago. A recent Canadian study has shown that genetic tests could have a positive economic effect while helping individual patients.

Cisplatin is used to treat a number of childhood cancers, but it can lead to hearing loss (ototoxicity). A genetic test that predicts the risk is available. If this was used and children at risk were switched to an alternative drug of equivalent price, this could save an average of $71,168 in societal costs per tested patient, or $19.6 million per year in Canada. While this is just a model, it shows the potential upside of using a genetic test.

However, using genetic tests isn't always that clear cut. There are many tests available on the market that tout their ability to identify your risk of developing cancer, diabetes, heart disease, Alzheimer's disease, and a range of other serious disorders. However, the American College of Obstetricians and Gynecologists has said that while genetic tests may be useful in the future, their time has not yet come, and they should only be used in clinical trials. This is because many genetic variations are only linked with a small increase in disease risk, and many of the tests have not gone through rigorous clinical trials, meaning that people could be worried for no reason. The college recommends that any tests should be discussed with someone who is an expert in the field.

So, the jury is still out on genetic testing. It has a lot of potential, and in the right hands, it can give excellent guidance on treatment, and even save money and save lives, but it is still in its infancy. It's something to watch. -- Suzanne Elvidge (email)