31 July 2006
ByAppeared in BioNews 369
Consumers should be wary of home DNA testing kits that claim to test whether the customer carries genes for certain diseases, according to an investigation by the US Government Accountability Office (GAO). The Senate Special Committee on aging, requested the year long investigation as part of the hearing 'At home DNA tests: Marketing Scan or Medical Breakthrough'. The report said the tests are misleading and lack predictive value.
The test results recommend expensive dietary supplements, and exercise information, to address their genetically determined risk of conditions such as heart disease and diabetes, without consulting a doctor. GAO suggests that this advice may exploit the customer.
GAO investigators purchased tests from four genetic testing websites, namely Market America, Genelex, Sciona and Suracell. They used DNA samples from an unrelated man and woman to create profiles of 12 fictitious characters with different age and lifestyle descriptions. The websites found different results for each profile. The GAO report explained that 'if the recommendations were truly based on genetic analysis, then the nine fictitious characters created using the female DNA should have received the same recommendations because the DNA came from the same source. Instead, they received a variety of different recommendations based on their fictitious lifestyles'.
Dr Kathy Hudson, director of the Genetics and Public Policy Centre, at Johns Hopkins University's Berman Bioethics Institute fears that unregulated at-home tests will do damage to the positive medical discoveries that arose from the Human Genome Project.
'Genetic testing is growing rapidly and holds great promise to improve health and healthcare', Hudson said. 'The information provided by genetic tests is used to make profound, sometimes life-and-death, decisions. It is therefore imperative that this information be accurate and reliable and relevant to a patient's health'.
Representatives from the companies that offer the at-home tests said they provide an important service and encourage customers to seek a medical professional to interpret the results. All said that they would welcome further oversight of their processes.
When asked how the company could offer different nutrition advice for the same DNA, Rosalynn Gill-Garrison, Chief Science Officer of Sciona, said that this was because the advice is largely tailored to the questionnaire about customer's current diet and health.
DNA testing kits have also been criticised in the UK. A meeting on genomics and public health held in London in January this year warned that using genetic tests to find out the risks of developing an illness was sometimes 'a waste of money'.