Personalized genetic tests may be flawed and have few health benefits, reports Ian Sample at the Guardian. Researchers from Erasmus University Medical Center in Rotterdam, the Netherlands, simulated genetic data from 100,000 people and then used 23andMe and DecodeMe's formulas to predict the risk of eight health conditions for that simulated population. ScienceDaily adds that this research was presented at the European Society of Human Genetics.
"When we looked at individual risk of disease, we saw enormous differences between the two companies," says Cecile Janssens in the Guardian. "A major problem with these tests is that they don't take other factors into account, such as your age, diet, exercise and whether you smoke, which in most cases have a greater impact on disease risk." Sample adds that those differences in risk could vary by more than 50 percentage points. Decode Genetics' Kári Stefánsson tells Sample that the Dutch team misinterpreted his company’s formula, and 23andMe's Brian Naughton says that a low risk of disease does not mean the risk calculation is incorrect; rather, a low risk is expected.