Genetics

The conventional Western classification systems of health conditions are based on flawed science shaped by reductionist, hierarchical, and profit-driven ideologies. THEN wants to create a new paradigm built upon principles drawn from systems science, the life course perspective, developmental neurobiology, and other evidence-informed studies.

As most readers are aware, it is widely believed that both within and without of psychiatry genetic factors play an important role in causing major psychiatric disorders such as schizophrenia, bipolar disorder, major depression, ADHD, autism, anxiety, and even post-traumatic stress disorder (PTSD). Twin studies provide the main pillar of support for this belief which is often, though mistakenly, presented as a scientific fact.

The huge impact of the MISTRA, in addition to the harmful and regressive social and political policy implications that flow from it, necessitates a detailed analysis of the “science” behind the study’s major claims and conclusions. Here I offer a new critique of this famous and influential “separated twin study.”

The story of the Genain quadruplets has long been cited as evidence proving something about the supposed hereditary nature of schizophrenia. But who wouldn’t fall apart after surviving a childhood like theirs? The doctors attributed their problems to menstrual difficulties or excessive masturbation — anything except abuse.

As the schizophrenia/psychosis recovery research continues to emerge, we discover increasing evidence that psychosis is not caused by a disease of the brain, but...

Autism is now simply assumed to represent a real, tangible, identifiable ‘thing.’ But no one is asking the obvious question: On what evidential basis can you conclude that autism represents a natural category that can be differentiated from other natural categories? According to the real science, autism should be seen as a fact of culture, not a fact of nature.

While a great deal of the excitement about advances in psychological treatments comes from the potential for research in neuroscience to unlock the secrets of the brain, many mental health experts would like to temper this enthusiasm. A special issue of the Behavior Therapist released this month calls into question the predominant conception of mental illnesses as brain disorders.

Twin studies supply the most frequently cited evidence in favor of important genetic influences on human behavioral differences. In an extremely small yet influential handful of studies, twin pairs were said to have been reared apart in different families. Twin researchers and others view this occurrence as the ultimate test of the relative influences of nature (genes) and nurture (environment). According to this view all behavioral resemblance between reared-apart MZ twin pairs (known as “MZA” pairs) must be the result of their 100% genetic similarity, because such pairs share no environmental similarity. But, far from being separated at birth and reared apart in randomly selected homes representing the full range of potential behavior-influencing environments, and meeting each other for the first time when studied, most MZA pairs were only partially reared apart, and grew up in similar cultural and socioeconomic environments at the same time.

Amid calls for a retraction, Lancet Psychiatry publishes articles criticizing the original finding and a response from the authors.

The latest issue of the journal Behavioral and Brain Sciences features several prominent researchers arguing that mental health concerns are not “brain disorders.”

When former NIMH chief Dr. Thomas Insel speaks, people listen. Dr. Insel famously criticized the DSM a couple of years ago for its lack of reliability. He notably broke ranks with the APA by saying there were no bio-markers, blood tests, genetic tests or imaging tests that could verify or establish a DSM diagnosis of schizophrenia, bipolar or schizoaffective disorder. However in a new article he announces research that claims to have found bona-fide physiological markers that identify specific "biotypes" of psychosis. This system could, purportedly, identify a person as possessing a specific biotype of psychosis, instead of a DSM-category diagnosis.

“The substantial hereditary component in schizophrenia,” a pair of researchers wrote in 1993, “is surely one of the two or three best-established facts in psychiatry.” But is it really? For mainstream psychiatry and psychiatric genetics, schizophrenia is “a severe mental disorder with a lifetime risk of about 1%, characterized by hallucinations, delusions and cognitive deficits, with heritability estimated at up to 80%,” or a “highly heritable neuropsychiatric disorder of complex genetic etiology.” Many commentators have challenged these claims, and some have challenged the concept of schizophrenia itself.

Neuroscience researchers find no differences in brain connectivity between children with diagnoses of autism, ADHD, and those with no diagnoses.

Can a renewed biopsychosocial approach, grounded in an updated philosophy, foster person-centered medicine, and psychiatry?

Human behavioral genetics and its allied field of psychiatric genetics are in trouble, as unfulfilled gene discovery expectations during the “euphoria of the 1980s” have continued to the present day, leading to researchers’ “nonreplication curse” dysphoria of the 2010s. In my recent book The Trouble with Twin Studies: A Reassessment of Twin Research in the Social and Behavioral Sciences, I presented a detailed argument that genetic interpretations of the common “classical twin method” finding that reared-together MZ twin pairs resemble each other more (correlate higher) for behavioral characteristics than do reared-together same-sex DZ twin pairs are invalid because, among other reasons, the twin method’s crucial MZ-DZ “equal environment assumption” (EEA) is false.

In recent months, two teams of researchers in the UK and the US published complementary findings about the epigenetic origins of schizophrenia that have scientific communities who indulge in ‘genetic conspiracy theories’ abuzz. While these results are intriguing, and no doubt involve pathbreaking research methodologies, this line of thought represents a decontextualized understanding both of the symptoms that are typically associated with schizophrenia, and their causes.

In a 1992 essay, British psychiatric genetic researcher Michael Owen wondered whether schizophrenia molecular genetic research would become the “graveyard of molecular geneticists.”1 Owen predicted that if major schizophrenia genes existed, they would be found within five years of that date. He was optimistic, believing that “talk of graveyards is premature.”2 Owen now believes that genes for schizophrenia and other disorders have been found, and was subsequently knighted for his work. Despite massively improved technology, however, decades of molecular genetic gene finding attempts have failed to provide consistently replicated evidence of specific genes that play a role in causing the major psychiatric disorders.

With the ties between traumatic childhood experiences and mental health issues, should we continue to focus on biological approaches?

Two generations of molecular genetic researchers have attempted, yet failed, to discover the genes that they believe underlie the major psychiatric disorders. The most recent failure is a molecular genetic study that was unable to find genes for symptoms of depression. Like most genetic researchers in psychiatry, the authors failed to consider the possibility that no such genes exist.

More than forty thousand papers have been published using functional magnetic resonance imaging (fMRI) technology to explore the brain. A new analysis of the common...

A recent commentary by Ganesan Venkatasubramanian and Matcheri Keshavan notes that efforts to identify biomarkers in people diagnosed with psychiatric disorders have been overwhelmingly...

In a philosophically rigorous article, Spanish researcher Marino Pérez-Álvarez examines the logic of attention-deficit hyperactivity disorder (ADHD).

Psychiatric molecular genetic research has failed to discover genes that underlie the major psychiatric disorders, the existence of which twin and adoption studies are assumed to have established. "Genome-wide complex trait analysis" (GCTA) was developed a few years ago as a means of solving what researchers call the "missing heritability" problem. One researcher believed that the new GCTA method would “drive a stake through the heart of” criticism of behavioral genetic theories and methods, and would finally put criticism of twin studies “to rest.” The opposite scenario appears to be playing out, however, as leading behavioral genetic and psychiatric genetic researchers struggle to prevent some recent negative GCTA findings and the obvious false assumptions underlying twin research from driving a stake through the heart of twin studies themselves.

In the light of the much trumpeted claims that recent research has identified genes for schizophrenia, it is important to review the track record of this type of endeavor. Despite thousands of studies costing millions of dollars, and endless predictions that the genetics of schizophrenia would shortly be revealed, the field has so far failed to identify any genes that substantially increase the risk of developing schizophrenia.

A new study, published in the journal Molecular Psychiatry, found no link between genetics and the occurrence of depressive symptoms.