The potentially debilitating effects of extreme anxiety, panic attacks, phobias and post-traumatic stress reactions are experienced by as many as one in four Americans at least once throughout their life time. Although there is a certain amount of fear learned from our environmental experience, research into the anxious behaviours of mice has shown that anxiety is also considerably influenced by genetic inheritance.
The genetic component associated with fear (or the lack thereof), has been identified as the coding of certain neurotransmitters responsible for inhibiting initial impulse and reaction response. Specifically, deficiencies in functional nerve cell receptors for gamma-amino butyric acid (GABA) (see Figure 1); have been shown to significantly increase anxiety and fear-related behaviour in mice. In humans, variability in serotonin re-uptake has also been shown to have a considerable impact on moderate to severe anxiety as well as depression.
Figure 1: Gamma-Amino Butyric Acid (GABA) -
Neurotransmitter responsible for controlling initial impulse and reaction response
Evidence derived from studies of adopted children and fraternal twins has left little doubt in the minds of researchers about the degree of genetic inheritance in anxiety. Consequently, as research into the effects of neurotransmitters on anxiety continues there is no doubt that the development of effective treatments for the symptoms of anxiety and stress will continue to improve.
Student Number: 42063331
Reference:
Clark, W.R. (2000). “Is our tendency to experience fear and anxiety genetic?” http://www.sciam.com/article.cfm?id=is-our-tendency-to-experi (Date Accessed: 09/04/09)
