Anxiety disorders genetic factors

The exact etiologies of PTSD and OCD are not known. It is hkely that abnormalities in several areas of hrain fnnctioning interact to canse these chronic anxiety disorders. Genetics may play arole in expression of PTSD and OCD, but environmental factors hkely are also involved. A nenrodevelopmental model of OCD has been proposed. ... 

To understand whether cognitive function and mood disorders are cooperatively influenced by genetic factors in AD and to know the potential impact that conventional neuroprotection can exert on mood disorders, we studied the effect of the therapeutic CNLA protocol on anxiety in AD and the differential APOE- and ACE-related responses distinguishing the influence of monogenic and bigenic variants on emotional conditions. 

The etiology of social anxiety remains unclear however, evidence suggests that developmental and genetic factors may predispose some individuals to social anxiety disorder. Adults with social anxiety disorder are more likely to report a history of childhood shyness and separation anxiety, limited social interaction during adolescence, and having had parents who placed great emphasis on the importance of the opinion of others. 

Anxiety reactivity to 35% CO2 inhalations has been reported not to be significantly influenced by clinical characteristics of the disorder such as baseline anxiety, frequency of panic attacks, severity of agoraphobia, duration of illness, and age (Perna et al. 1994). On the other hand, several studies suggest a relevant role of genetic factors in 35% CO2-induced panic attacks, and it has been concluded that C02-induced panic might be considered a phenotypic expression of a genetic vulnerability to panic disorder even before the clinical onset of panic disorder (e.g., Perna et al. 1995 Bellodi et al. 1999). 

As with most other anxiety disorders, the cause of OCD remains far from certain. There seems to be a genetic factor that makes people more likely to develop OCD because first-degree relatives (that is, people like siblings and parents) of patients who have OCD show a statistically increased rate of OCD-type symptoms even if they do not experience the full-blown version of the disorder. Also, studies of identical and fraternal twins show that where one twin has OCD, the other twin has a 67% chance... 

Lesch et al. demonstrated that a functional 5-HTT promoter polymorphism is associated with the factor neuroticism in the revised NEO personality inventory (51). Specifically, individuals who carry the s/s (short promoter repeat) alleles of the 5-HTT, as compared with individuals with s/l (long) or 1/1 alleles, have increased neuroticism. Extension of these genetic studies to anxiety disorders by the same authors showed no differences in 5-HTT genotype-distribution between anxiety patients and comparison subjects, but among anxiety patients, carriers of the s/s alleles exhibited higher neuroticism scores (52). 

Hettema JM, Prescott CA, Myers JM, Neale MC, Kendler KS. The structure of genetic and environmental risk factors for anxiety disorders in men and women. Arch. Gen. Psychiatry 2005 62 182-189. 

The mitral valve prolapse probably does not cause anxiety, but it has been found that MVP and anxiety disorders often coexist. This may be due to some common underlying genetic factor. 

The differential diagnosis of anxiety disorders includes medical and psychiatric illnesses and certain drugs. Family studies show that SAD can be inherited, with a threefold increase in the rate of SAD in relatives of patients. Behavioral inhibition, characterized by wariness, decreased social interaction, and withdrawal, is a genetic trait that may contribute to SAD. " Patients with SAD commonly report having overprotective parents. Parental dysfunction and abuse are potential risk factors for developing SAD. "... 

Merikangas KR (2002) Genetic and other vulnerability factors for anxiety and stress disorders. In Davis KL, Charney D, Coyle JT, Nemeroff C (eds) Neuropsychopharmacology— the fifth generation of progress. Lippincott Williams and Wilkins, Philadelphia, pp 867-882... 

A number of other factors, including genetic or biological factors, that are possibly associated with the development of psychiatric disorders, have been explored. In a retrospective study of 110 patients with chronic hepatitis C, those with the apolipoprotein E e4 allele, the inheritance of which may be associated with several neuropsychiatric outcomes, were more likely than those without this allele to have psychiatric referrals and neuropsychiatric symptoms, in particular irritability, anger, anxiety, or other mood symptoms, during interferon alfa treatment... 

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