Here is an interesting article that shows
studies that are determining that schizophrenia is caused by a
combination of different genetic factors, and is actually eight
different genetic disorders that work together - in various combinations thereof - to create the differing presentations of schizophrenia (i.e., positive and/or negative symptoms).
Mark Strozier/Getty
BREAKTHROUGH
09.16.14
Schizophrenia Isn’t One Disorder but Eight
In perhaps the most important
study in schizophrenia’s history, researchers have identified that it is
not a single inherited disorder as previously believed, but rather
eight separate genetic disorders.
Schizophrenia is perhaps the most misunderstood mental illness, but a research team at the Washington University School of Medicine in St. Louis has just come one step closer to understanding how it works.
After analyzing the DNA of over 4,000 patients with schizophrenia,
the investigators of the study have determined that schizophrenia is not
a single inherited disorder as previously believed, but rather eight
separate genetic disorders that can combine into “clusters” which carry
significant risks for schizophrenia.
As senior investigator Dr. C.
Robert Cloninger notes, “[genes] don’t work by themselves. They
function in concert much like an orchestra, and to understand how
they’re working, you have to know not just who the members of the
orchestra are but how they interact.” Rather than focusing on the
individual genes that have been associated with schizophrenia, this team
looked instead at the interactions between genes in order to isolate
the causes of the illness.
In an audio interview,
Cloninger observes that this multi-faceted etiology of schizophrenia
matches the plurality and complexity of its symptoms: “There isn’t just
this one kind of schizophrenia but actually several different syndromes
where some people have positive symptoms like hallucinations and
delusions [and] others have negative symptoms where they’re not able to
think logically and these different syndromes are associated with
different groups of genes.” Instead of looking for one gene that could
account for all of the possible configurations of schizophrenic
symptoms, Cloninger and his colleagues looked at the way in which
different configurations of genetic variations produce different
symptoms in individual patients.
Washington University’s new
research could be the most important breakthrough in schizophrenia
research since the illness was first diagnosed. Their findings hint
toward new treatment possibilities for an illness whose symptoms are
almost as difficult to alleviate as they are to understand. And the
clarity of their discovery could finally put the persistent cultural
myths surrounding schizophrenia to rest and help the public better
understand this severe mental illness.
Early treatments for schizophrenia were as ineffective as they were dangerous. As Rachel Whitehead of Rethink Mental Illness writes for the Guardian,
early 20th-century physicians treated schizophrenic patients with
injections of sulfur and oil. In the 1930s and ’40s, physicians
struggled to find a more tenable treatment. As an article in the Canadian Journal of Psychiatry
notes, Swiss psychiatrists attempted to treat schizophrenia by inducing
sleep for long periods of time, often resulting in pneumonia and death.
Other psychiatrists attempted to treat schizophrenia with carbon
dioxide gas and artificially-induced comas. In the 1950s, the first
antipsychotic drug was invented and treatment for schizophrenia has
revolved around the use of pharmaceutical drugs ever since.
“[Genes] don’t work by themselves. They function in concert much like an orchestra, and to understand how they’re working, you have to know not just who the members of the orchestra are but how they interact.”
Currently,
schizophrenic patients are treated with a combination of antipsychotic
medications (e.g. Clozapine) and therapeutic treatment, most notably
cognitive behavioral therapy (CBT). While schizophrenia is much more
treatable now than it was a century ago, antipsychotic medications still
carry significant side effects. Clozapine, for instance, can lower a
patient’s white blood cell count to dangerous levels, substantially
reducing the body’s ability to fight infection. And as the National Alliance on Mental Illness
(NAMI) notes, Clozapine is “hard on the body and causes a risk of
diabetes, weight gain, myocarditis, and other medical concerns that need
to be planned for.”
Potentially serious side effects aside, recovery from schizophrenia can take years of treatment. One study in the American Journal of Psychiatry
found that “the overall rate of recovery during the early years of the
illness is low,” with under 14 percent of subjects maintaining “full
recovery criteria for 2 years or longer.” Another study, in the British Journal of Psychiatry,
examined long-term outcomes, finding that only 16 percent of people
with “early unremitting cases” of schizophrenia could recover in the
later years of the illness. Both studies concur that the symptoms of
schizophrenia are eminently treatable with around half of schizophrenic
patients finding substantive relief from their symptoms, but “full
recovery” remains an elusive and arduous task. Many people with
schizophrenia will die from suicide and unnatural causes before they can complete or even receive treatment. As one review article in the Archives of General Psychiatry notes, nearly 5 percent of people with schizophrenia will die by suicide alone.
After a century of ineffective treatments, risky medications, and
stalled genetic research, the new findings from Washington University
could be an important step forward in treating schizophrenia. For one,
the treatment of schizophrenia could be further individuated to match
each individual patient’s needs. By sorting the patients in their study
by their symptomatology, the research team at Washington University
could identify which “clusters of genetic variations” led to which
symptoms. As Dr. Igor Zwir notes in the Washington University press release, “it soon may be possible to target treatments to specific pathways that cause problems.” And as research into gene therapy for schizophrenia
continues, Washington University’s findings will give researchers new
pathways to pursue to target symptoms of schizophrenia. In the future,
the Washington University study may mark the tipping point in the
successful treatment of schizophrenic patients.
In addition to potentially revolutionizing the diagnosis and
treatment of schizophrenia, this discovery could finally put to rest
longstanding rumors about the causes of schizophrenia. Because past
researchers typically looked for a single gene that caused
schizophrenia, scientists knew that the illness was inherited but
struggled to understand what other imbricating factors could account for
it. The National Institute of Mental Health,
for instance, observes that having a relative with schizophrenia
significantly increases its risk but leaves plenty of room open for the
influence of “environmental factors” such as malnutrition.
The Johns Hopkins Health Library,
too, notes “many factors—genetic, behavioral, and environmental—play a
role in the development of this mental health condition.” While
environmental factors certainly play a role in the development of any
genetic disorder—schizophrenia included—the continued mystery of
schizophrenia’s genetic origins has perhaps left too much room open for
rampant speculation about the sort of environmental factors that cause
the illness.
Some still believe the mid-20th-century rumors that
schizophrenia is caused by bad parenting, alcohol abuse, or other forms
of trauma, so much so that many resources on schizophrenia still find it
necessary to explicitly refute these myths. NAMI notes that 6 percent
of people still believe that “people diagnosed with schizophrenia did
something to cause their condition.” These myths about the causation of
schizophrenia stigmatize it, allowing the public to willfully
misunderstand it by blaming it instead on the families who suffer the
most from its symptoms. Despite the fact that millions of people and
approximately 1 percent of Americans
have schizophrenia, misinformation about the illness promotes the
belief that schizophrenia is the result of some sort of moral failing
and not genetic variation.
Despite the fact that millions of people and approximately 1 percent of Americans have schizophrenia, misinformation about the illness promotes the belief that schizophrenia is the result of some sort of moral failing and not genetic variation.
And
the ignorance that continues to surround schizophrenia actively
compounds its treatment on a cultural level. As NAMI notes in a report
on the perception of schizophrenia, the “lack of knowledge” surrounding
schizophrenia constitutes a “public health crisis” inasmuch as
investment in treatment options requires widespread public awareness
about the disorder. Only a quarter of Americans feel as if they are
familiar with schizophrenia, with only Lou Gehrig’s disease and multiple
sclerosis ranking lower on the scale. A substantial percentage of
Americans, too, still fear people with schizophrenia at work or in their
personal lives even if they are undergoing treatment. NAMI believes
that this “knowledge gap” must be closed to promote a culture in which
people view schizophrenia as a treatable illness. If more people could
recognize schizophrenic symptoms and openly care for those who suffer
with schizophrenia, more people with the illness might seek treatment
during the critical early stages.
The new research from Washington University could be influential in
closing this knowledge gap, as it seems to be the most definitive
information about the origins of schizophrenia uncovered so far. In a
country where six times as many people believe false rumors about
schizophrenia as suffer from it, the conclusive discovery of the genetic
clusters that contribute to schizophrenia should finally start to bury
past misconceptions about the illness. In addition to possibly
transforming future approaches to the treatment of schizophrenia,
Washington University’s recent findings could also finally give a
misinformed public the clarity it needs to promote widespread
understanding of this devastating mental illness.
Thank-you for posting this enlightening article about new research in schizophrenic disorders!
ReplyDeleteMarcia Weisbrot
marciaweisbrot.blogspot.com