Results vary in genetic home test kits
Researchers at Emory's Rollins School of Public Health analyzed and compared DNA test results from three direct-to-consumer personal genome testing companies (23andMe, deCODEme, and Navigenics) and found that results not only varied from company to company but were contradictory for certain traits in certain individuals. The complete findings are available in the online edition of Genetics in Medicine.
"Although two of the companies that we studied are no longer operating, genotyping and sequencing is becoming less expensive, and testing such as this is increasingly popular," says epidemiologist Cecile Janssens, who led the study. "The methods used for predicting these types of results are an important concern."
Using the prediction methods of the three companies, which were obtained from their websites, the Emory team calculated predicted risks for six diseases: type 2 diabetes, prostate cancer, celiac disease, Crohn's disease, age-related vision loss, and abnormal heart rhythm.
The variations in predicted risks were explained by several factors, including the fact that the three companies applied different mathematical formulas. The formulas of two companies led to an overestimation of risks and even predicted risks that were higher than 100%.
"Our study provides insight into the methodology and performance of risk estimation for personal genome tests," says Janssens. "Future efforts to design predictive models will benefit from understanding the strengths and limitations of these current models and formulas."
Related Links
"Direct-to-consumer genetic testing kits vary in predictions of disease risk"
Study in Genetics in Medicine
Biosketch: A. Cecile J.W. Janssens
Emory Genetics Laboratory
