Back on the old h20 there was a discussion dealing with capital punishment. I offered this comment that may be supported by recent discoveries.
No human can judge the causes of a person murdering another. What
would you do if researchers discovered a genetic defect that made
a person likely to murder. What if it was discovered that
administering a drug could correct this genetic defect? How would
you feel if your son was executed for committing murder and a year
later such a drug was discovered?
The vast majority of murderers are male. That tells you that there
is something about being male that predisposes a person to being a
murderer. There is no harm in keeping murderers safely incarcerated
until such time as a cure for this is discovered.
UW finds genetic root of aggression
Trait increases likelihood of crime
By SHIRLEY DANG
of the Journal Sentinel staff
Last Updated: Aug. 1, 2002
A gene variant found in one-third of males may make abused or neglected boys prone to aggression later in life, a new study by University of Wisconsin-Madison researchers shows.
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"There is a cycle of violence where maltreated children grow up to maltreat others. We found that this depends very strongly on their genetic makeup," said study co-author Terrie Moffitt, professor of psychology at UW-Madison. The findings were published today in the journal Science.
Conversely, the study suggests that another version of the gene in two-thirds of males protects them from the stress of traumatic events, partly explaining why some children who are abused do not become aggressive.
"People have come to think of genes that are lurking inside of us that are going to give us cancer, or going to give us a disease. What we've found is a gene that prevents people from breaking down under high stress," Moffitt said. "It's the protective effect that to me is exciting."
Madison researchers worked with scientists from King's College in London and the University of Otago in New Zealand to examine 442 males from birth to 26 years.
Of the subjects, 154 suffered childhood maltreatment, including parental rejection and moving from foster home to foster home. Thirty-three of the subjects were severely maltreated, meaning they were sexually or physically abused.
Roughly a third of the subjects had a form of a gene, or genotype, that results in low levels of the brain enzyme called monoamine oxidase A, or MAOA.
The enzyme clears away excess amounts of three types of neurotransmitters, or signal chemicals in the brain: norepinephrine, dopamine and serotonin.
"It returns the brain back to a healthy balance," Moffitt said.
Maltreatment occurred among those with both versions of the gene. But the group that was severely abused and produced little of the brain-clearing enzyme, 12% of the study, was responsible for 44% of the violent convictions among all participants.
Among the same group, 85% developed anti-social behavior, which included lying, bullying, stealing, repeatedly violating the law and showing no remorse for aggressive acts.
Only a quarter of the abused subjects who had high levels of the enzyme displayed these behaviors.
The research does not prove, however, that those with the high risk genotype will become violent criminals.
"There has been a lot of anxiety about genetic labeling. This kind of research highlights it's not genetic determinism but genetic vulnerability to environmental risk," said Alfred Blumstein, professor and director of the National Consortium on Violence Research at Carnegie Mellon University in Pennsylvania.
Identifying those with a genetic risk of aggression and history of abuse could allow treatment to be focused more effectively, he said.
"We know that child maltreatment will increase likelihood of aggression. We know that not everybody develops it," said Emil Coccaro, professor and director of the Clinical Neuroscience and Psychopharmacology Research Unit at the Pritzker School of Medicine at the University of Chicago.
The paper helps explain the difference between those who veer off into aggression after being abused in childhood, he said.
In 2000, more than 879,000 children were abused or neglected in the United States, according to the National Child Abuse and Neglect Data System.
Maltreated children have a 50% greater risk for criminality, according to the journal study.
"The essence of this story," Blumstein said, "is that genes are not determinative on their own. It's the interaction between a genetic propensity or potential that gets enacted by particular environmental experiences or exposures."
Appeared in the Milwaukee Journal Sentinel on Aug. 2, 2002.