see Recommendations from the EGAPP Working Group: does genomic profiling to assess type 2 diabetes risk improve health outcomes?
An evaluation of several commercial tests for type 2 diabetes published in this issue found little to no benefit to patients. An accompanying systematic review and recommendation statement conclude there currently is no advantage to such testing and therefore discourage its use at this point. After reviewing the published literature and information made available on company websites, the Evaluation of Genomic Applications in Practice and Prevention Working Group (EWG) concluded that there is no evidence of analytical validity (reproducible test performance) or clinical utility for currently available tests. Several companies offer genomic testing for type 2 diabetes, either through a health-care provider or direct to consumers. Evaluation of test performance proved difficult because the EWG found that it could not even identify the testing platform or methodology used in some cases. Looking at testing both for the general population and for high-risk groups, they detected little, if any, ability to evaluate or classify individual risk. Specifically, they found insufficient evidence to recommend testing for the transcription factor 7–like 2 (TCF7L2) gene marker. Although the gene has been demonstrably linked to a higher risk of developing type 2 diabetes, there is no evidence that knowledge of the presence of the gene variation could improve health outcomes. The EWG states that, to be useful, genomic testing must be shown to have predictive value superior to that of traditional risk factors. Therefore, until advances in the clinical validity of these genomic panels can be demonstrated, their use is discouraged. —Karyn Hede, News Editor
