Therapygenetics

Therapygenetics refers to a branch of psychiatric genetic research looking at the relationship between specific genetic variants and differences in the level of success of psychological therapy.

Background
Thalia Eley and her research team coined the term in 2011. The field is parallel to pharmacogenetics, which explores the association between specific genetic variants and the efficacy of psychiatric drug treatments. Therapygenetics work also relates to the differential susceptibility hypothesis which proposes that individuals have a genetic predisposition to respond to a greater or lesser extent to their environment, be it positive or negative.

History
The 2011 paper marked the first use of the term, although previous studies looking for associations between specific genetic variants and response to psychological therapy were conducted. The study used data collected from 359 children from Reading, UK, and Sydney, Australia. Analyses showed that a variation in the Serotonin Transporter Promotor Polymorphism (5HTTLPR) – previously associated with anxiety and response to stress – correlated with the efficacy of cognitive behavioural therapy (CBT), a common treatment method for anxiety disorders. Those with the shorter version of this polymorphism were 20% more likely to be free of their anxiety disorder when assessed at follow-up, several months after the end of treatment with CBT. These individuals also showed a greater reduction in symptoms over the period of treatment.

Research directions
Beevers and McGeary reviewed the concept and its research, giving their support for the future of therapygenetics research as a means of enhancing the efficacy of psychological treatments. Eley et al are exploring therapygenetics in relation to anxiety. There is scope for this form of research across disorders and treatments. It is hoped that this type of work may eventually inform personalised treatment, decreasing treatment time and improving the mental health of those with psychiatric conditions.

The following year we extended our focus to a single nucleotide polymorphism in the Nerve Growth Factor gene (NGF rs6330) and brain-derived neurotrophic factor (BDNF rs6265). Both genes are implicated in synaptic plasticity, response to stress and are widely expressed in brain areas involved in mood and cognition. Analyses showed no significant association between response to CBT and the polymorphism within the BDNF gene. For the NGF polymorphism, those with one or more copies of the T allele were significantly more likely to be free of their anxiety disorder when assessed at follow-up. These effects remained even when other clinically relevant covariates were accounted for.

Video clips

 * Excellence in Research Award: Genes for Therapy - Macquarie University
 * Channel 10 (Australia) Nightly News: “New Anxiety Test”