Serotonin transporter makes your response to psychotherapy?

Nowadays, many studies are published to investigate the relationship between gene and response to a certain treatment. If their statements are reliable, patients can avoid trying ineffective treatment using gene examination in advance. It is decisive, especially in the choice of some medication which are potentially poisonous.

Today, I read an article suggesting that serotonin transporter diversity is relevant to the response to cognitive behavioral therapy. In this study, hundreds children with anxiety disorder were given cognitive behavioral therapy. The subjects who have Short/Short (S/S) genotype of Serotonin transporter achieved good improvement of the mental status after treatment compared to ones with other types.

Molecular Psychiatry: Therapygenetics: The 5HTTLPR and response to psychological therapy

There is a hypothesis that Serotonin transporter subtypes are relevant to vulnerability to stress. Who with S/S are likely to be anxious in unusual situations. I was personally involved in an experiment when I was a college student, so I believe this hypothesis. The majority of Japanese, including myself, has S/S genotype, much different from American.

If this result is true, Japanese are more likely to be sensitive to cognitive therapy than American. It is certain that patients who were vulnerable to the change of environment will recover when their inner cognition is adjusted. A sensitive person may be flexible in preferable circumstance.

However, this study can be interpreted differently. People with other genotype than S/S are less likely to be anxious. Thus, patients with anxiety disorder without S/S genotype have some other factor to cause such disease. Anxiety disorder is not a single concept. Social phobia, Post traumatic stress disorder, or other kind of biological impairment would be included. Such patients are difficult to be healed with standard treatment strategy. The difference in response rate to therapy is possible to due to the cause of the disease, not subtype of the gene.

Mental disorders are hardly to be classified definitely. This fact makes discussion complex.