Genetic testing and personalised nutrition
16 April 2009
HGC statement on genetic testing and personalised nutrition
The HGC welcomes the statement issued by SACN on genetic testing and personalised nutrition. Genetic tests that claim to be able to give nutritional health information, but have not been robustly and independently evaluated, are a concern for the HGC.
The HGC believes that test providers need to be able to provide evidence that the genetic tests they offer can reliably and accurately, predict what they claim to be able to predict. The link between a gene and a condition or trait should be proven for all genetic tests, including nutrigenetic tests, before they are sold to the public and proof of this link should be made available to consumers. The sale of genetic tests without this proven level of clinical validity can give rise to unnecessary anxieties about health or give an individual a false level of reassurance. With nutrigenetic tests in particular, this could lead to an over-consumption or avoidance of certain food groups, which could cause potential harm to the individual and lead to further costs to the NHS.
The HGC advises any individual who is thinking about taking a nutrigenetic tests to obtain the following information first:
• general information on genetic testing and specific information on the nutrigenetic test including the evidence of the link between the gene and the condition/trait and whether this link has been published in a peer-reviewed academic journal
• the measures the test provider will take to ensure the confidentiality of their biological samples and personal records
• how they will be provided with the genetic test results and who they will be able to contact if they don’t understand the results
• information on the limitations of the test so that they are aware of the level of significance that they can attribute to the results of the test
• whether their biological sample will be used for any secondary purposes or if their personal details will be passed on to any third parties
The Commission believes that individuals taking a test should be aware that the interaction between genes and environment factors, such as food, is complex and constantly changing which makes interpretation of nutrigenetic tests very difficult and in some cases impossible without knowing these environmental factors. Consumers should also understand that some nutrigenetic tests are less predictive than the results they might receive for other genetic tests.
The HGC would like to reiterate the importance for the NHS to provide certain genetic tests, where the genetic variation has a significant health impact on an individual and the clinical validity and utility of the test has been extensively proven. The test for the single gene disorder, Phenylketonuria is such a test. Individuals who inherit this metabolic disorder, who are left untested and untreated can have affected brain development. A simple test at birth and subsequent controlled diet can prevent this. These tests, where the clinical validity and utility have been extensively studied, should not be confused with other tests that lack such thorough evaluation.
The HGC is currently developing a common framework of principles for direct genetic tests and it is expected that the principles will cover the provision of nutrigenetic tests to the public, outside a framework of professional healthcare. The Commission has worked extensively on direct genetic tests and has strong international links and is therefore well placed to develop a set of principles that can be applied internationally that will build on and support existing guidelines and legislation or will identify where there are gaps in current regulation. The Commission will be consulting on a draft set of principles in Spring 2009 and would welcome feedback from interested parties including regulators, test providers and those who have concerns about the interests of consumers.
Click here for more information on the common framework of principles for direct genetic tests or alternatively if you wish to be consulted on the principles please email emma.burton@dh.gsi.gov.uk
The Commission has produced a list of questions to aid individuals when considering the purchase of any type of health related direct genetic tests. Click here to read this list.