Mental Illness: It's Not in Your Genes

Many neuropsychiatric ailments that are assumed to have a major genetic component don't seem to have one.

Even before the Human Genome Project wrapped up in April 2003, scientists have worked overtime to find the gene or genes responsible for autism, schizophrenia, Alzheimer's, ADHD, alcoholism, depression, and other ailments "known" to have major genetic components.


The problem is, many neuropsychiatric ailments that are assumed to have a major genetic component don't seem to have one.

More than a decade after the sequencing of the human genome, there is still no reliable genetic test for autism, Alzheimer's, schizophrenia, or any other major neuropsychiatric disorder (except for Huntingon's disease, for which there was already a test, prior to the Human Genome Project). In late 2012, scientists claimed (in a paper in Molecular Psychiatry) that a genetic test for autism had been devised. In actuality, the "test," a classifier developed using data from 237 single-nucleotide polymorphisms in 146 genes, proved unreliable. The software had been trained on one set of human genes (from central Utah) and tested against another set (from northern Europe); it correctly predicted if you were of northern European descent, not whether you might be at risk for autism.

Over 1,000 genes are known to be differentially expressed in the autistic brain, but as of yet there is no way to predict in advance who will differentially express the genes in question.

Meanwhile, more than 80 candidate genes for alcoholism have been identified—in the fruit fly. Likewise, hundreds of genes have been "implicated" in schizophrenia (the database at www.szgene.org currently contains 8,788 polymorphisms pertaining to 1,008 genes). But we are no closer to having reliable genetic markers for schizophrenia (much less depression) than we were in the 1930s, when the "feeble minded" were compulsorily sterilized (not just in Nazi Germany but in the U.S. and most western countries) to keep their inferior genes from propagating.

The problem is, there's no convincing evidence that schizophrenia (much less depression, or even alcoholism) is genetic in origin. To be sure, many neuropsychiatric problems (including schizophrenia) are familial, and most people blindly equate "runs in the family" with genetics. But the fact is, wealth, poverty, child abuse, eating/drinking habits, and many other things "run in families," yet no one seriously suggests high net worth (for example) is genetic.

The ultimade proof, supposedly, of the genetic basis of schizophrenia comes in the form of twin studies that have been done showing a high rate of concordance for schizophrenia in monozygotic (identical) twins versus fraternal (non-identical or dizygotic) twins. But as psychologist Jay Joseph points out in The Gene Illusion: Genetic Research in Psychiatry and Psychology Under the Microscope (2003, PCCS Books), the twin-study data are not particularly convincing when held up to scrutiny. Although early twin studies by Franz Kallman found concordance rates as high as 69% (which Kallman changed to 86% after applying unwarranted "age correction factors"), later studies have found much lower rates, and in fact the later the study, the lower the rate. By the late 1980s, some studies were reporting pairwise concordance rates of under 20% for schizophrenia in twins. The largest such study found:

Pairwise concordance rates for schizophrenia (11.0% for MZ and 1.8% for DZ) indicated environmental influence with apparent genetic liability.

Why shouldn't we believe the earlier twin studies? Aside from small sample size (thus low statistical power) there are substantial issues around lack of blinding, uneven diagnostic capability (not just regarding schizophrenia, but monozygosity of twins), and researcher bias. (Kallman was an avowed eugenecist.) But a more serious issue, according to Jay Joseph and other critics of twin studies, is that the "equal environment assumption" that underlies all such studies simply isn't valid. The equal-environment assumption says that identical twins are not exposed to an environment that's significantly different than the one fraternal twins are exposed to. (If there are environmental differences, then those differences, rather than genetic differences, might explain any difference in outcome between identical and fraternal twins.) A wide range of evidence casts doubt on the equal environment assumption. Indeed, whenever identical twins are given special treatment by parents (or teachers, total strangers, each other, etc.) based on similar appearance, the equal-environment assumption goes out the window. Joseph believes environmental confounds undermine every twin study, and on this basis alone, he condemns such studies as fundamentally unreliable.

Whether or not Joseph is right, the fact remains that scientists have failed miserably to find genes for schizophrenia, depression, and other major mental disorders. The most recent failure was reported in the April 2013 edition of Biological Psychiatry, wherein Karin Hek and 85 (yes, 85) coauthors tell of performing a genome-wide association study involving 34,549 individuals suffering from depression. Only one single nucleotide polymorphism (SNP) was "suggestive" of an association with depression, and that SNP didn't map to a known gene. With a certain degree of resignation, the authors concluded:

The results suggest that only a large sample comprising more than 50,000 subjects may be sufficiently powered to detect genes for depressive symptoms.

And yet the Hek writeup begins with: "Depression is a heritable trait that exists on a continuum of varying severity and duration." Which is exactly what the study did not show.

The truth is much harder to report. There is, as yet, no known gene for anything psychiatric. And the indications are that none will be found.

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Political division is nothing new. Throughout American history there have been numerous flare ups in which the political arena was more than just tense but incideniary. In a letter addressed to William Hamilton in 1800, Thomas Jefferson once lamented about how an emotional fervor had swept over the populace in regards to a certain political issue at the time. It disturbed him greatly to see how these political issues seemed to seep into every area of life and even affect people's interpersonal relationships. At one point in the letter he states:

"I never considered a difference of opinion in politics, in religion, in philosophy, as cause for withdrawing from a friend."

Today, we Americans find ourselves in a similar situation, with our political environment even more splintered due to a number of factors. The advent of mass digital media, siloed identity-driven political groups, and a societal lack of understanding of basic discursive fundamentals all contribute to the problem.

Civil discourse has fallen to an all time low.

The question that the American populace needs to ask itself now is: how do we fix it?


Discursive fundamentals need to be taught to preserve free expression

In a 2017 Free Speech and Tolerance Survey by Cato, it was found that 71% of Americans believe that political correctness had silenced important discussions necessary to our society. Many have pointed to draconian university policies regarding political correctness as a contributing factor to this phenomenon.

It's a great irony that, colleges, once true bastions of free-speech, counterculture and progressiveness, have now devolved into reactionary tribal politics.

Many years ago, one could count on the fact that universities would be the first places where you could espouse and debate any controversial idea without consequence. The decline of staple subjects that deal with the wisdom of the ancients, historical reference points, and civic discourse could be to blame for this exaggerated partisanship boiling on campuses.

Young people seeking an education are given a disservice when fed biased ideology, even if such ideology is presented with the best of intentions. Politics are but one small sliver for society and the human condition at large. Universities would do well to instead teach the principles of healthy discourse and engagement across the ideological spectrum.

The fundamentals of logic, debate and the rich artistic heritage of western civilization need to be the central focus of an education. They help to create a well-rounded citizen that can deal with controversial political issues.

It has been found that in the abstract, college students generally support and endorse the first amendment, but there's a catch when it comes to actually practicing it. This was explored in a Gallup survey titled: Free Expression on Campus: What college students think about First amendment issues.

In their findings the authors state:

"The vast majority say free speech is important to democracy and favor an open learning environment that promotes the airing of a wide variety of ideas. However, the actions of some students in recent years — from milder actions such as claiming to be threatened by messages written in chalk promoting Trump's candidacy to the most extreme acts of engaging in violence to stop attempted speeches — raise issues of just how committed college students are to
upholding First Amendment ideals.

Most college students do not condone more aggressive actions to squelch speech, like violence and shouting down speakers, although there are some who do. However, students do support many policies or actions that place limits on speech, including free speech zones, speech codes and campus prohibitions on hate speech, suggesting that their commitment to free speech has limits. As one example, barely a majority think handing out literature on controversial issues is "always acceptable."

With this in mind, the problems seen on college campuses are also being seen on a whole through other pockets of society and regular everyday civic discourse. Look no further than the dreaded and cliche prospect of political discussion at Thanksgiving dinner.

Talking politics at Thanksgiving dinner

As a result of this increased tribalization of views, it's becoming increasingly more difficult to engage in polite conversation with people possessing opposing viewpoints. The authors of a recent Hidden Tribes study broke down the political "tribes" in which many find themselves in:

  • Progressive Activists: younger, highly engaged, secular, cosmopolitan, angry.
  • Traditional Liberals: older, retired, open to compromise, rational, cautious.
  • Passive Liberals: unhappy, insecure, distrustful, disillusioned.
  • Politically Disengaged: young, low income, distrustful, detached, patriotic, conspiratorial
  • Moderates: engaged, civic-minded, middle-of-the-road, pessimistic, Protestant.
  • Traditional Conservatives: religious, middle class, patriotic, moralistic.
  • Devoted Conservatives: white, retired, highly engaged, uncompromising,
    Patriotic.

Understanding these different viewpoints and the hidden tribes we may belong to will be essential in having conversations with those we disagree with. This might just come to a head when it's Thanksgiving and you have a mix of many different personalities, ages, and viewpoints.

It's interesting to note the authors found that:

"Tribe membership shows strong reliability in predicting views across different political topics."

You'll find that depending on what group you identify with, that nearly 100 percent of the time you'll believe in the same way the rest of your group constituents do.

Here are some statistics on differing viewpoints according to political party:

  • 51% of staunch liberals say it's "morally acceptable" to punch Nazis.
  • 53% of Republicans favor stripping U.S. citizenship from people who burn the American flag.
  • 51% of Democrats support a law that requires Americans use transgender people's preferred gender pronouns.
  • 65% of Republicans say NFL players should be fired if they refuse to stand for the anthem.
  • 58% of Democrats say employers should punish employees for offensive Facebook posts.
  • 47% of Republicans favor bans on building new mosques.

Understanding the fact that tribal membership indicates what you believe, can help you return to the fundamentals for proper political engagement

Here are some guidelines for civic discourse that might come in handy:

  • Avoid logical fallacies. Essentially at the core, a logical fallacy is anything that detracts from the debate and seeks to attack the person rather than the idea and stray from the topic at hand.
  • Practice inclusion and listen to who you're speaking to.
  • Have the idea that there is nothing out of bounds for inquiry or conversation once you get down to an even stronger or new perspective of whatever you were discussing.
  • Keep in mind the maxim of : Do not listen with the intent to reply. But with the intent to understand.
  • We're not trying to proselytize nor shout others down with our rhetoric, but come to understand one another again.
  • If we're tied too closely to some in-group we no longer become an individual but a clone of someone else's ideology.

Civic discourse in the divisive age

Debate and civic discourse is inherently messy. Add into the mix an ignorance of history, rabid politicization and debased political discourse, you can see that it will be very difficult in mending this discursive staple of a functional civilization.

There is still hope that this great divide can be mended, because it has to be. The Hidden Tribes authors at one point state:

"In the era of social media and partisan news outlets, America's differences have become
dangerously tribal, fueled by a culture of outrage and taking offense. For the combatants,
the other side can no longer be tolerated, and no price is too high to defeat them.
These tensions are poisoning personal relationships, consuming our politics and
putting our democracy in peril.


Once a country has become tribalized, debates about contested issues from
immigration and trade to economic management, climate change and national security,
become shaped by larger tribal identities. Policy debate gives way to tribal conflicts.
Polarization and tribalism are self-reinforcing and will likely continue to accelerate.
The work of rebuilding our fragmented society needs to start now. It extends from
re-connecting people across the lines of division in local communities all the way to
building a renewed sense of national identity: a bigger story of us."

We need to start teaching people how to approach subjects from less of an emotional or baseless educational bias or identity, especially in the event that the subject matter could be construed to be controversial or uncomfortable.

This will be the beginning of a new era of understanding, inclusion and the defeat of regressive philosophies that threaten the core of our nation and civilization.