Genes, environment and schizophrenia—new study finds the placenta is the missing link

May 28, 2018, Lieber Institute for Brain Development
Fetus in utero, between fifth and sixth months. Image credit: Wikipedia.

Hiding in plain sight, new research shines a spotlight on the placenta's critical role in the nature versus nurture debate and how it confers risk for schizophrenia and likely other neurodevelopmental disorders including ADHD, autism, and Tourette syndrome. This new scientific frontier, with far-reaching implications for maternal and child health, creates the possibility that scientists can more accurately predict who is at risk of mental illness, and develop strategies to prevent or lessen their occurrence by increasing the resiliency and health of the placenta.

The study, "Convergence of biology and genetic risk for schizophrenia," was led by researchers at the Lieber Institute for Brain Development and published in Nature Medicine. "For the first time, we have found an explanation for the connection between early life complications, genetic risk, and their impact on mental illness and it all converges on the placenta," said Daniel R. Weinberger, who led the team of investigators on the study and is CEO of the Lieber Institute for Brain Development (LIBD).

In contrast to prior studies that focused on how genes related to behavioral disorders directly alter prenatal brain development, this novel research found that many genes associated with risk for schizophrenia appear to alter early brain development indirectly, by influencing the health of the placenta. The research showed that these genes are "turned on" in the placenta during complicated pregnancies and signal a placenta under duress.

While the subject of myth and ritual in many cultures, the placenta remains a scientifically neglected human organ, despite its essential role for supplying nutrients and chemicals critical for normal prenatal development. Indeed, the placenta is the only organ removed from a human body that is not routinely sent to the laboratory for examination.

For over a quarter of a century, brain development during pregnancy and shortly after birth has remained central to a hypothesis that schizophrenia is a neurodevelopment disorder. However, the biological mechanisms involved were poorly understood. Previous studies have shown that genetic variants alone increase the odds of developing schizophrenia by only a fraction, while early life complications during pregnancy and labor can increase risk by up to 2-fold. The Lieber Institute investigators studied over 2800 adult individuals, 2038 of whom had schizophrenia, of various ethnic backgrounds from four countries, including the USA, Europe and Asia. All had undergone genetic testing and were surveyed for obstetrical history information.

Researchers found a prominent interaction between genes associated with risk for schizophrenia and a history of a potentially serious pregnancy complication. Individuals having high genetic risk and serious early life complications have at least a fivefold greater likelihood of developing schizophrenia in comparison to individuals with similarly high but no history of serious obstetrical complications. This led to a series of analyses of gene expression in multiple placenta tissue samples, including samples of placenta from complicated pregnancies that include preeclampsia and intrauterine growth restriction. The results showed a striking and consistent turning on of the schizophrenia genes in these placentae and the more they were turned on, the more the placenta showed other signs of being under stress, for example, being more inflamed.

A Clue to Higher Male Risk for Schizophrenia

One of the many mysteries of developmental behavioral disorders, including schizophrenia, autism, ADHD, dyslexia, and Tourette Syndrome is why their incidence is 2-4 times greater in males than in females. The Lieber Institute team findings may shed light on this mystery. They found that the genes turned on in the placenta from complicated pregnancies were dramatically more abundant in placentas from male compared with female offspring. The placenta appears to be at least part of the explanation for the sex bias associated with these disorders.

"The surprising results of this study make the placenta the centerpiece of a new realm of biological investigation related to how and the environment interact to alter the trajectory of human ," said Weinberger.

Further research into this emerging frontier of clinical medicine will advance the understanding of the biological interplay between placental health and neurodevelopment. There is a potential to discover novel approaches to therapeutic treatments and prevention strategies, and ultimately reduce the incidence of neurodevelopmental behavior disorders.

Explore further: Assisted reproduction may up risk of placental anomalies

More information: Gianluca Ursini et al, Convergence of placenta biology and genetic risk for schizophrenia, Nature Medicine (2018). DOI: 10.1038/s41591-018-0021-y

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not rated yet May 28, 2018
Really interesting!
5 / 5 (2) May 28, 2018
"...developmental behavioral disorders, including schizophrenia, autism, ADHD, dyslexia, and Tourette Syndrome is why their incidence is 2-4 times greater in males than in females..."

-which correlates to

"male psychopaths are 7 times more common than female..."

Psychopaths are arguably the most dangerous and detrimental to society so these researchers ought to be focusing on THEM.

Psychopaths are born not made and they are untreatable. Further

"The high incidence of [psycho]pathy in human society has a profound effect on the rest of us who must live on this planet, too, even those of us who have not been clinically traumatized. The individuals who constitute this 4 percent drain our relationships, our bank accounts, our accomplishments, our self-esteem, our very peace on earth."

-Identify them. Constrain them. Perhaps prenatally. Is there any better reason for an abortion?
5 / 5 (2) May 28, 2018
Psychopaths are the people who can walk into a school, look a child in the face, and shoot them without emotion. They are the ONLY type of mental defective who can do this.

We need guns to protect us from psychopaths. And we need reliable ways of keeping guns out of the hands of psychopaths.

One of the major hurdles, in all seriousness, is that the lawmakers we rely on to pass laws against psychopaths, are themselves psychopaths.

"... many psychopaths are able to reach very high positions in life. It is only over time that their associates become aware of the fact that their climb up the ladder of success is predicated on violating the rights of others."Even when they are indifferent to the rights of their associates, they are often able to inspire feelings of trust and confidence."
5 / 5 (2) May 28, 2018
We might say that our political systems are designed to select for psychopaths. Little wonder, as they were designed by them to secure power and enhance their ability to victimize.

In this respect there is little difference among them, including the democratic process wherein we are presented with a limited choice and are then made to feel guilty when they are exposed and we are reminded that we voted them in.

Even religion - the psychopath god promises to grant every wish and when he doesn't it is our fault for not being devout enough.

They are everywhere and have been for millennia. This is the source and the depth of the human disease. And effectively removing their poisonous effect on society can only be accomplished by an AI capable of discerning truth from lies, and acting accordingly.

Their advantage has always been the fact that telling lies is always easier than exposing them. Only a machine can correct this inbalance.
5 / 5 (1) May 29, 2018
Otto, you've been reading too much pop-psychology again.

The individuals who constitute this 4 percent

That's an exaggeration.

" while for legal or other practical purposes an arbitrary cut-off point on trait scores might be used, there is actually no clear scientific evidence for an objective point of difference by which to label some people "psychopaths"; in other words, a "psychopath" may be more accurately described as someone who is "relatively psychopathic"."

In actuality, less than 1% of the people are psychopaths to the extent that the scare-mongerers paint them, and with one fault comes others - most severely psychopathic individuals aren't actually intelligent enough to pass as normal people and they end up in jails and mental institutions.

If one person in a thousand is a "true psychopath", the probability of you personally knowing one is about 15%
5 / 5 (1) May 29, 2018

A 2008 study using the PCL:SV found that 1.2% of a US sample scored 13 or more out of 24, indicating "potential psychopathy". The scores correlated significantly with violence, alcohol use, and lower intelligence. A 2009 British study by Coid et al., also using the PCL:SV, reported a community prevalence of 0.6% scoring 13 or more. The scores correlated with younger age, male gender, suicide attempts, violence, imprisonment, homelessness, drug dependence, personality disorders (histrionic, borderline and antisocial), and panic and obsessive–compulsive disorders.

In other words, it's only the rare psychopath that ends up in a high career position, because they're generally too broken and ill-behaved to climb up the social ladder. They "out" themselves too early. The pop-psych moral panic mongering about how every other CEO is a psycho and the workplaces are full of narcissists and psychos is just for selling books
5 / 5 (1) May 29, 2018
That quote of course was not mine but from the article I referenced. You ought to read it before offering such uninformed (ignorant) opinions as
most severely psychopathic individuals aren't actually intelligent enough to pass as normal people and they end up in jails and mental institutions
-If you had you would have read this...

"Even the profoundly unscrupulous are not all the same. Some people - whether they have a conscience or not - favor the ease of inertia, while others are filled with dreams and wild ambitions. Some human beings are brilliant and talented, some are dull-witted, and most, conscience or not, are somewhere in between. There are violent people and nonviolent ones, individuals who are motivated by blood lust and those who have no such appetites."

-One wonders what your motivation is for wanting to minimize such a threat? Doesn't it bother you that there are such people in society, the madoffs, weinsteins, and kilpatricks? Not rare - common.
5 / 5 (1) May 29, 2018
the probability of you personally knowing one is about 15%
-And yet I've known several, in my family, the workplace, social settings.

True there is no clear definition yet. They're a spectrum just like autism. But we would have a much clearer picture if there was as much research applied to psychopathy as there has been to autism.

"Imagine - if you can - not having a conscience, none at all, no feelings of guilt or remorse no matter what you do, no limiting sense of concern for the well-being of strangers, friends, or even family members. Imagine no struggles with shame, not a single one in your whole life, no matter what kind of selfish, lazy, harmful, or immoral action you had taken."

The condition is just as real as autism. The fact that they can be as functional as anyone else does not negate the fact that they are doing so without the normal suite of emotions that normal people have.

Deception and victimization is the purpose of a psychopaths life.
5 / 5 (1) May 29, 2018
BTW the 4% quote as well as the others above originated with

"Martha Stout, Ph.D., a clinical psychologist in private practice, served on the faculty in psychology in the department of psychiatry at Harvard Medical School for twenty-five years."
not rated yet May 29, 2018
I'm not sure I understand where psychopathy fits in....Is this a natural consequence of complications during pregnancy or are they trying to paint a broader stroke?
not rated yet May 29, 2018
I'm not sure I understand where psychopathy fits in....Is this a natural consequence of complications during pregnancy or are they trying to paint a broader stroke?
Studies like the above may provide answers we can use if we have the resolve to do so.
5 / 5 (1) May 31, 2018
That quote of course was not mine but from the article I referenced.

Then maybe you ought to give references and links in advance, instead of assuming I'm going to just take your word for it. I'm not a mind reader you know.

And yet I've known several, in my family, the workplace, social settings.

What's more likely is that you're labeling people psychopaths because there's some sort of disagreement between you, and it's an easy out from admitting yourself being in the wrong.

You ought to read it before offering such uninformed (ignorant) opinions

"Martha Stout, Ph.D., a clinical psychologist in private practice

I'm going to make an ad-hominem and say she's one of those scare-mongerers who do it to sell books, and you just bought it hook, line, and sinker. Other psychologists and latest research clearly disagree with her.

About 0.6 - 1.2% are -potentially- psychopaths, meaning they exhibit higher than 50% of the diagnostic criteria.
5 / 5 (1) May 31, 2018
No, we are not swimming in psychopaths

Swedish researcher Karolina Sörman thinks some of us display a morbid curiosity about psychopaths.

According to SIFER (the Norwegian Centre for Research and Education in Forensic Psychiatry) from 0.5 to 1 percent of the population could be psychopaths.

One reason why people recognise the image of prolific numbers of psychopaths in society is that many of the characteristics of a psychopath, such as lack of empathy, cold-heartedness and manipulative conduct are found among many besides the psychopaths

But if your ex, your boss or the chairman in your housing collective seems to exhibit one of these traits that doesn't make them psychopaths.

"In order to be defined as a psychopath a person has to have many of these traits,"

More to the point, they must exhibit the traits consistently, and not just towards you. Many are cold and callous to people they dislike
5 / 5 (1) May 31, 2018
There's just this popular habit of taking (often competely made up) lists of traits and criteria, typically published in womens' magazines or other popular tabloids, and then applying them to people around you. It's kinda like hypochondriasis: imagining you have some disease to explain your own anxiety, except applied outwards.

So you get into a bit of panic, or maybe you were outraged by something, and buy the book that confirms your idea, and suddenly - psychopaths are everywhere! Everyone who's ever been a little mean to you, brushed you off, cut you in line... everyone's a psychopath, or a narcissist, or whatever is the "asshole-du-jour". Back in the 18th century it was witches.

These observations are aided along by the fact that nobody is a saint. Everyone's a dick to someone, and a friend to another - so one person can call you a manipulative devil while another is your best buddy you'd never betray - and that doesn't make you or anyone else a psychopath.
5 / 5 (1) May 31, 2018
Btw. as far as hypochondria and percieving things goes:


Apophenia (/æpoʊˈfiːniə/) is the tendency to perceive connections and meaning between unrelated things.[1] Confirmation bias is a variation of apophenia. The term (German: Apophänie) was coined by psychiatrist Klaus Conrad in his 1958 publication on the beginning stages of schizophrenia.

Conspiracy theories, seeing psychopaths everywhere, or finding that everything in the news or history is a part of a clever master plan, could be a sign of your own mental illness.
not rated yet Jul 18, 2018
The Otto Ghost is so absolutely SPOT ON as to how awful and destructive the "Nightmare people" really are. "Eikka" is a rude pig with a stupid name. She is so crappy to Otto Ghost I had to join to sign on to say "Eikka you are a mean unimaginative hater.
not rated yet Jul 27, 2018
My lame quote was solely meant to give you a wake-up call/ mirror/sampling of what your own attack writing /Occult Agenda: Demean humiliate discredit opinion of others at any cost because you appear to have deficits of a conscience and an actual opinion.
Only enjoy trying to eviscerate others, entrails and all, to experience schadenfreude. Your ilk: seems to constitiute about a 4% presense online.

Where a comment should appear, here is your blistering closed analysis discrediting O.G.with a Google found quote turned on O.G. on things you cannot know:

Erikka to O.G. about O.G. in front of the public: "Conspiracy theories, seeing psychopaths everywhere, or finding that everything in the news or history is a part of a clever master plan, could be a sign of your own mental illness.".

Erikka: U should be sued for defamation under the tort of libel. U are not above the law. I will report here. Easy cases to win if untrue and evidenced. This one is GOLD.

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