Scientists have discovered a gene responsible for determining the effectiveness of actions on a person's placebo.
Israeli and American researchers have found that the response to placebo generates a gene that triggers the production of dopamine, known as the "hormone of pleasure". In the study found the enzyme catechol-O-methyltransferase (COMT), providing the body's response to dopamine.
It was found that the gene that encodes COMT, has several different mutations Val158Met. A specific segment of DNA of each pair of chromosomes can have the amino acid methionine (Met) or valine (Val).
People with a pair of Met/Met with the introduction of placebo dopamine levels were 3-4 times higher than the level of dopamine those who present a pair of Val/Val. This area dopamine is the area of the prefrontal cortex, which is responsible for the functions of cognition, decision making and human behavior in society.
The researchers then examined the relationship between the mutation Val158Met and the response to placebo in practice. Patients with irritable bowel syndrome, divided by groups. At first no therapy was not carried out, and the other was allowed to take a placebo. It was found that the maximum effect of placebo had people who had two copies of the methionine. And those who had two copies of valine were observed to have the highest resistance to the placebo effect.
According to scientists, if confirmed by further research, these findings will be a significant advancement in evidence-based medicine.