Describing the causes of heart disease as a thousand piece puzzle, scientists led by Indrani Halder of the University of Pittsburgh, have admitted to putting at least one piece in place.
Halder says the gist of her study, which attempted to connect genetics, emotions and health, is that anger and depression could be genetic.
Studying around 550 women of European descent, across the U.S, Halder and her colleagues noted the connections between a gene associated with serotonin levels and their mutations, with levels of aggression and hostility.
The researchers found that the angriest women were most likely to have variations in a gene that affects serotonin receptors on brain cells.
Says Halder, "In essence, this gene makes an important protein that helps nerve cells communicate."
The new study shows that women with one alteration in the HTR2C gene, which is noted, to be linked to serotonin, were less aggressive, while women with a different alteration in the gene were more physically aggressive. A third alteration in the gene didn't seem to affect aggression or hostility.
According to Dr. James Grisolia, a neurologist at Scripps Mercy Hospital in San Diego, "Serotonin function within the brain has many effects, both in men and women.
"Serotonin plays a key role in sleep, emotional state and physical well-being. Men and women walk into my office on a daily basis with anxiety, depression or physical complaints such as insomnia, dizziness, or memory loss that respond to selective serotonin reuptake inhibitors [SSRIs]", he adds.
Halder opines that her research which looked at the relationship between variations in the serotonin receptor gene and anger and hostility, have found a genetic marker that may be may be useful for predicting a person's predisposition to diseases such as hypertension, glucose metabolism and heart diseases.