- Study looked at short and long alleles, or variants, of gene 5-HTTLPR
- This is involved in the regulation of a chemical known as serotonin
- Research found the short allele amplifies emotional reactions during both good and bad environments
People with a specific gene variant, which affects the way the brain chemical serotonin works, smiled and laughed more while watching cartoons or amusing films. And data from the experiments indicated that people with the short variations of the gene showed greater positive emotional expressions in general.
In the study by Northwestern University in Illinois, the researchers looked at short and long alleles - or variants - of the gene 5-HTTLPR. This is involved in the regulation of serotonin, a neurotransmitter involved in depression and anxiety.
While previous research has found that those with the short version were more sensitive to negative emotions than those with the long version, this study found they were more responsive to the emotional highs of life as well. 'Having the short allele is not bad or risky,' said researcher Dr Claudia Haase. 'Instead, the short allele amplifies emotional reactions to both good and bad environments.
'People with short alleles may flourish in a positive environment and suffer in a negative one, while people with long alleles are less sensitive to environmental conditions.'