Generalized anxiety disorder (GAD) is characterized by exaggerated and uncontrollable worry or tension about everyday events, at a level more severe than warranted by the situation. It is estimated that 5.7% of people suffer from GAD over the course of their lives with 3.1% of people suffering it at any one time. Genetic factors are thought to be behind about a third (31%) of the risk of GAD, with environmental factors making up the rest of the risk. Little is known about the genes responsible for a greater risk of GAD and how they interact with environmental factors. Researchers from Harvard Public School of Health in Boston, U.S. looked into the links between a variation in the RGS2 gene, exposure to the 2004 Florida hurricane and the development of GAD. 607 adults sent samples of DNA from a cheek swab in by post and were asked about their experience of the hurricane, their levels of social support and their GAD symptoms. The study found that after allowing for age, sex, ancestry, hurricane exposure and social support each variation in the RGS2 gene was associated with a doubling of the risk for GAD.
Koenen, Karestan C. ... [et al] - RGS2 and generalized anxiety disorder in an epidemiologic sample of hurricane-exposed adults Depression and Anxiety April 2009, 26(4), 309-315