Because of the excess of happy substances in the brain, the family produced 5 generations of anti-social violent men

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Written by Seven Kings

Fifty years ago, a woman with a tragic experience came to the University Hospital of Nijmegen in the Netherlands to ask for help

Her family has 8 violent men, including her sons and brothers

How can there be so many sociopaths in a family? After being tortured by these relatives to the point of helplessness, she turned to researchers in the hope that they could find the source

The lady was received by Dutch geneticist Han Brunner

Brunner found that the family had been violent for five consecutive generations, dating back to a male ancestor

Brunner argues that the violent tendencies of these related male offenders may be related

But by 1988, the family's problems began to get worse, with violent men continuing to abuse their loved ones and the women of the family coming to Brunner for help

Fortunately, there were advances in gene mapping technology in that era, and the girls volunteered to let Brunner study their genes

The MAOA gene encodes the protein monoamine oxidase A, which breaks down three important neurotransmitters: norepinephrine, dopamine, and serotonin

Norepinephrine improves concentration and is associated with the "fight or flight" response in an emergency; Dopamine can bring the thrill of addiction, similar to the "hi" when the game wins; Serotonin is often referred to as a happy neurotransmitter because it makes people feel peaceful and happy, a bit like the feeling you feel

Interestingly, serotonin has also been linked to

All in all, these three neurotransmitters can give people positive, pleasant feelings

(Image source: pxhere)

You might think that since these three substances can make people feel awake and happy, the more and the longer they are, the better?

On the contrary, after these three neurotransmitters have completed their mission, the normal human brain will reabsorb or break them down, controlling the content of these three substances within
a reasonable level.

If they are maintained at a high level, they will make people "run wild"
.

Brunner speculates that mutations in the MAOA gene in these violent men cause the brain to fail to break down these three neurotransmitters, making them more likely to commit violent acts
in stressful situations.

For example, two violent men in the family committed arson after the death of a close relative
.

Because the MAOA gene is located on the X chromosome, and men have only one X chromosome from their mother, they have a higher tendency
to be violent if something goes wrong with the X chromosome given by the mother.

Conversely, because girls have two X chromosomes, even if the X chromosome from one parent has a violent version, its effect can be diluted by the normal version on the other X chromosome
.

The MAOA gene is located on the X chromosome, a mutation recessive inheritance
of the Dutch family.

(Image source: wikipedia)

Sure enough, the violent men all carried this genetic mutation, the men who did not have violent tendencies in the family did not carry this mutation, and the women in the family also carried the violent version but did not have violent tendencies
.

Consistent with Brunner's speculation, the violent man had high levels of norepinephrine, dopamine and serotonin in his urine, indicating that his body was unable to metabolize these neurotransmitters
.

In 1993, Brunner and colleagues published the study in Science, and the paper has received more than 2,000 citations
.

This is the first time that antisocial personality disorder has been linked to genes
.

However, mutations in the MAOA gene passed down from generation to generation in this Dutch family are very rare in the population, and later studies found that most sociopaths have another common version of the MAOA gene that is weaker in function, MAOA-3R
.

(Image source: publicdomainpictures.
net)

In 2004, another report published in Science referred to MAOA-3R as the "warrior gene" because cold-blooded sociopaths can become better fighters
.

The article immediately sparked a discussion about the gene of violence
.

Of course, carrying a low-featured version of MAOA doesn't mean that one has to be antisocial, because the acquired role is just as powerful
.

(Image source: wikimedia)

Researcher Avshalom Caspi and colleagues at King's College London followed more than 1,000 people with "warrior genes" for 20 years and published the results in a 2002 issue of Science
.

The study found that not all people who carry high-risk genes will go down the path of crime, and only those who suffered abuse in childhood are more likely to develop antisocial behavior and become "perverts" when they grow up
.

In other words, violence can only be passed on
through violence.

A genetics researcher is a case in point
.

Jim Fallon, a neurologist at the University of California, Irvine, discovered a few years ago that his brain resembled that of an antisocial personality offender
.

After genetic sequencing, he found that he had a "warrior gene.
"

Jim Fallon (Credit: Daniel A.
Anderson /University Communications)

Fallon's family is full of criminals, and seven of his relatives have been charged with murder
.

For example, his cousin Lizzie Borden hacked his father and stepmother
to death with an axe.

And one of his great-grandfathers in the 17th century once killed his mother, and the case was written into a book
.

However, he himself has no violent tendencies
.

Fallon says that whether a person with a high-risk gene becomes a true sociopathic criminal depends on childhood experiences, and if the brain "sees a malicious world" growing up, the only reasonable response is to become evil as
well.
"
If the brain feels a normal world, then it becomes normal
.

”

He himself had a happy childhood, so instead of having antisocial tendencies, he had a lot of prosocial behavior
.

However, the "warrior gene" also has a negative performance in him, that is, he "does not feel the warmth of human feelings" when interacting with others
.

But Fallon points out that "warrior genes" aren't always negative either, and they allow people to stay calm in high-pressure environments and not be manipulated
by emotions.

Fallon says he scores high on cognitive empathy, but low on emotional empathy, which means he understands others rationally but doesn't empathize emotionally, so he often becomes a "trash can" for emotional catharsis for friends and family because he listens but is not bound
by empathy.

(Image source: pxhere)

Because of the upsurge of the "warrior gene" paper in 2004, China has also carried out research on "warrior gene", and the results found that compared with the environment, the contribution of "warrior gene" is not worth mentioning
.

Meng Huaqing, a national natural science foundation of China and a national peer review expert on science and technology in colleges and universities, and the chief physician of the First Affiliated Hospital of Chongqing Medical University, once led a team to conduct research on
THE MAOA gene.

They studied 400 juvenile offenders in Hunan, Sichuan and Guangdong provinces whose crimes included murder and robbery, some of whom had already embarked on criminal paths before the age of
14.

(Image source: wikimedia)

The researchers divided juvenile offenders into two groups, one for violent crimes and one for those who were not violent
.

They compared the DNA
of these violent, nonviolent, and non-criminal record peers.

The results found that there was no significant difference in the MAOA gene between Violent Juvenile Offenders and ordinary children in China, that is, the "warrior gene" did not play a role
in predicting juvenile delinquency in China.

However, there is a high correlation
between juvenile delinquency and smoking, drinking and school violence in China.

Meng Huaqing told the South China Morning Post that after a few years, the Chinese government gradually cut off funding for this research project because there was no evidence
that MAOA had caused juvenile delinquency.

He said genes have little impact on aggression compared to environmental factors such as lower social support, physical abuse and family instability
.

Meng Huaqing also said that other teams have made similar discoveries
.

(Image source: wikimedia)

Zhang Xiaohui, a researcher at the State Key Laboratory of Cognitive Neuroscience and Learning at Beijing Normal University, believes that it is not surprising that the Chinese government has abandoned research funding for the genes of specific warriors, because the brain is extremely malleable, "THE INFLUENCE OF DNA and life after birth on behavior is five-to-five, and genes generally play a joint role; To find the warrior genes, you have to find a stable pattern across generations," as the Dutchman mentioned at the beginning of the article
.

Brunner, who discovered the correlation between the MAOA gene and the antisocial personality, warned against the superstitious belief in the "warrior gene
.
"
Another piece of genetic material that affects half the world's population and makes carriers more violent, he said, is the Y chromosome
.

Does that mean that people who carry the Y chromosome, that is, men, become criminals? Apparently not
.

"Genes load crime, and the environment pulls the trigger", this is perhaps the best summary of the inextricable connection between nature and nurture
.

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.

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