The role of the FTO gene in the relationship between depression and obesity. A systematic review.

Abstract

Depression and obesity are major global health problems that frequently co-occur. The FTO gene has one of the strongest links with obesity and high body mass index (BMI) in humans. Besides, this gene is highly expressed in the brain, may play a role in the nervous system, and could confer risk for depression, although scarce literature is available in this respect. We perform a systematic review of the relationship between FTO and both conditions. We selected original articles with observational design or reviews, where depression was assessed with ICD-10, DSM-5 or previous versions, published from 2012 (when the first related paper was published) to November 2020, performed in adults, in English or Spanish and having an optimal methodological quality (evaluated with SIGN checklist). Five original studies were finally included. The results regarding the role of FTO in depression-obesity comorbidity were inconclusive. This leads us to endorse further research covering the role of this gene on both conditions, emphasising a more precise characterization of depression, in order to confirm this role.