Doesn't that say environment has a strong influence?
Just to be clear, nobody is claiming that this gene "causes" psychopathic behavior, just that some people have a genetic predisposition. Most people with the mutant MAOA gene are not violent criminals, and not all violent criminals have the MAOA gene.
On the other hand, it is saying that given the right environmental triggers, those with the mutant MAOA gene are much more likely to become violent criminals. You see the same thing with alcoholics and other drug addicts: environment plays a big role, but some people are naturally more predisposed to it than others.
There could be a strong correlation with measured intelligence and education.
In 1919, Georg Lukacs became Deputy Commissar for Culture in the short-lived Bolshevik Bela Kun regime in Hungary. He immediately set plans in motion to de-Christianize Hungary. Reasoning that if Christian sexual ethics could be undermined among children, then both the hated patriarchal family and the Church would be dealt a crippling blow. Lukacs launched a radical sex education program in the schools. Sex lectures were organized and literature handed out which graphically instructed youth in free love (promiscuity) and sexual intercourse while simultaneously encouraging them to deride and reject Christian moral ethics, monogamy, and parental and church authority. All of this was accompanied by a reign of cultural terror perpetrated against parents, priests, and dissenters.
Hungary’s youth, having been fed a steady diet of values-neutral (atheism) and radical sex education while simultaneously encouraged to rebel against all authority, easily turned into delinquents ranging from bullies and petty thieves to sex predators, murderers, and sociopaths.
http://www.americanthinker.com/articles/2007/02/cultural_marxism.html
CROWDING INTO THE BEHAVIORAL SINK
Calhoun, J. B. (1962). Population density and social pathology. Scientific American, 206(3), 139-148.
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Aggression. Normally in the wild, male rats will fight other male rats for dominant positions in the social hierarchy. These fights were observed among the more aggressive rats in this study as well. The difference was that here, unlike in their natural environments, top-ranking males were required to fight frequently in order to maintain their positions and often the fights involved several rats in a general brawl. Nevertheless, the strongest males were observed to be the most normal within the center pens.
However, even those animals would sometimes exhibit “signs of pathology; going berserk; attacking females, juveniles, and less active males; and showing a particular predilection—which rats do not normally display—for biting other rats on the tail” (p. 146).
...
Sexual deviance. These probers also refused to participate in the natural rituals of mating. Normally, a male rat will pursue a female in heat until she escapes into her burrow. Then, the male will wait patiently and even perform a courtship dance directly outside her door. Finally, she emerges from the burrow and the mating takes place. In Calhoun’s study, this ritual was adhered to by most of the
sexually active males except the probers. They completely refused to wait and followed the female right into her burrow. Sometimes the nests inside the burrow contained young that had failed to survive, and it was here that late in the study the probers turned cannibalistic. Another group of male rats was termed the pansexuals because they attempted to mate with any and all other rats indiscriminately. They sexually approached other males, juveniles, and females that were not in heat. This was a submissive group that was often attacked by the more dominant male rats, but did not fight for dominance.
Reproductive abnormalities. Rats have a natural instinct for nest building. In this study, small strips of paper were provided in unlimited quantities as nest material. The females are normally extremely active in the process of building nests as the time for giving birth approaches. They gather the material and pile it up so that it forms a cushion. Then they arrange the nest so that it has a small indentation in the middle to hold the young. However, the females in the behavioral sink gradually lost their ability (or inclination) to build adequate nests. At first they failed to form the indentation in the middle. Then, as time went on, they collected fewer and fewer strips of paper so that eventually the infants were born directly on the sawdust that covered the pen’s floor.
More at http://www.edmondschools.net/Portals/3/docs/Terri_McGill/READ-Crowding.pdf
Don’t know about Lombroso’s work, but over the years I’ve noticed that people who resemble birds make great salesman. Like birds, they literally do not give up.