Genetic test feedback with weight control advice: study protocol for a randomized controlled trial

BACKGROUND Genetic testing for risk of weight gain is already available over the internet despite uncertain benefits and concerns about adverse emotional or behavioral effects. Few studies have assessed the effect of adding genetic test feedback to weight control advice, even though one of the proposed applications of genetic testing is to stimulate preventive action. This study will investigate the motivational effect of adding genetic test feedback to simple weight control advice in a situation where weight gain is relatively common. METHODS/DESIGN First-year university students (n = 800) will be randomized to receive either 1) their personal genetic test result for a gene (FTO) related to weight gain susceptibility in addition to a leaflet with simple weight control advice ('Feedback + Advice' group, FA), or 2) only the leaflet containing simple weight control advice ('Advice Only' group, AO).Motivation to avoid weight gain and active use of weight control strategies will be assessed one month after receipt of the leaflet with or without genetic test feedback. Weight and body fat will be measured at baseline and eight months follow-up. We will also assess short-term psychological reactions to the genetic test result. In addition, we will explore interactions between feedback condition and gene test status. DISCUSSION We hope to provide a first indication of the clinical utility of weight-related genetic test feedback in the prevention context. TRIAL REGISTRATION Current controlled trials ISRCTN91178663.