The Insanity Virus

Schizophrenia has long been blamed on bad genes or even bad parents. The real culprit, they claim, is a virus that lives entwined in every person's DNA.

Sixty million years ago, a lemurlike animal—an early ancestor of humans and monkeys—contracted an infection. It may not have made the lemur ill, but the retrovirus spread into the animal’s testes (or perhaps its ovaries), and once there, it struck the jackpot: It slipped inside one of the rare germ line cells that produce sperm and eggs. When the lemur reproduced, that retrovirus rode into the next generation aboard the lucky sperm and then moved on from generation to generation, nestled in the DNA. “It’s a rare, random event,” says Robert Belshaw, an evolutionary biologist at the University of Oxford in England. “Over the last 100 million years, there have been only maybe 50 times when a retrovirus has gotten into our genome and proliferated.” [...]

Through this research, a rough account is emerging of how HERV-W could trigger diseases like schizophrenia, bipolar disorder, and MS. Although the body works hard to keep its endogenous retroviruses under tight control, infections around the time of birth destabilize this tense standoff. [...]

The first, pivotal infection by toxoplasmosis or influenza (and subsequent flaring up of HERV-W) might happen shortly before or after birth. That would explain the birth-month effect: Flu infections happen more often in winter. The initial infection could then set off a lifelong pattern in which later infections reawaken HERV-W, causing more inflammation and eventually symptoms. This process explains why schizophrenics gradually lose brain tissue. It explains why the disease waxes and wanes like a chronic infection. And it could explain why some schizophrenics suffer their first psychosis after a mysterious, monolike illness.

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13 Responses:

  1. strspn says:

    Previously... but wait! Alternative hypotheses: the top bracket tax rate (quick historical review) and, get this: the CDC in 2007 pretty abjectly lied about it!

    • David Gurba says:

      In all honesty I'm trying to be subjective as my uncle is a vietnam vet and schizophrenic since 1971.

      I dont buy this much as an explanation because I'm not aware of viruses that the body cannot fight off. If I understand the quoted text it sounds like the author believes the virus has successfully co-mingled with our DNA, yet preserved itself enough to mimic traits of a long-term viral infection.

      But, most viruses ... take the common cold our body is able to suppress eventually. Some viruses like AIDS seem to have tricks to bypass our immune system's notification system. But, our body always attempts to fight these diseases (even if they lose).

      My problem with this argument is that while it appears schizophrenia has traits of a viral infection -- I am not aware of anyone being completely free of schizophrenia. People can learn to live with the symptons, but to my knowledge once your schizophrenic you've got it for life. But then why can't our body 'eventually' fight it off if it is merely a viral infection.

      thank you for the informative blurb. i am a long time reader -- 1st time poster. and i donated $5 to your legal troubles a while back.

      • headlouse says:

        There are other of viruses that we can't fight off and that go into remission and reemerge: herpes, hpv, etc. In any case, the virus doesn't even have to ever reemerge to cause permenant phyisical changes to the brain. Toxioplasmosis is a known bacteria that effects the brain of mice drastically - and possibly has effects on humans.

        Also, our genes are littered with the remenants of past viruses long dead and misc noncoding DNA. As such, this theory seems at least plausible.

        • drhoz says:

          Toxoplasmosis, caused by Toxoplasma gondii. And it's a protozoan, not a bacterium. Otherwise, quite right. And just look at what damage chickenpox can do in adults, once it's established in your ganglial nerves and comes back as shingles.

      • alzdran says:

        If you read the article, you'll also see that there's permanent neurological damage done by the virus, and that it may be related to other diseases, like MS.

        Retroviruses which successfully get into our DNA can't be successfully banished, though they're expression can be hindered. Much of the concept here is that the disease's expression would be influenced by a number of factors, suppressed by medications, and this would give us an avenue to attempt to address it early without it having a chance to do a lot of damage first.

        This disease would be an incredible example of "successfully getting into our DNA", as it is present throughout the population, but not always expressed: The ultimate in parasitic success; the genes get reproduced with every new member of the species.

      • mentallill says:

        You're infected with several viruses that your body cannot fight off: those viruses are known as herpes viruses; "herpes simplex" is one of them, but chickenpox is a more typical example: you've had it as a child (ideally), it can re-erupt as shingles, and it's generally not a big deal.

        What these guys are suggesting is that schizophrenia, in addition to being simply bad luck, is also connected to genetic material that happens to have originally, many hundreds of generations ago, been a retrovirus: in other words, it's partly genetic.

        HERV-W is no longer a viable virus: while its defective instructions still produce what looks like virions, these aren't good enough to successfully infect other cells: it cannot spread from a human that has the embedded genes to another human that doesn't (for starters, it's embedded in all humans alive today).

        The rule of thumb for schizophrenia is that one third of patients, without treatment, will continue exhibiting psychotic symptoms for the rest of their lives; one third will get better after the initial episode, but eventually redevelop symptoms; and one third will have a single episode and live out the rest of their lives without symptoms. It's not true that you're stuck with it for life.

        It's probably true, as the article suggests, that removing embedded retroviruses from the human genome is relatively harmless and will make many diffuse disorders a lot better. It's also significantly harder than curing HIV, which is not (yet) embedded, so that's a bit of a back-burner medical issue.

        The assertion that better treatment of concomitant infections that trigger the HERV-W bursts might help is useless: keeping kids in bubbles, away from toxoplasmosis, is impossible, and keeping kids away from the ubiquitous herpes viruses such as chickenpox is dangerous, as they'd only catch them as adults instead.

        The rest of the article's your typical popular science "let's laugh at the mentally ill" material: electroshock therapy (which actually works) thrown in with the more medieval treatment options, "insanity" in the title, the standard "haha, my theory is so groundbreaking that they thought _I_ was insane" joke, and the rather odd dichotomy in the title: rather than blaming schizophrenia on bad genes, it's really bad genes (that happen to have been a retrovirus thousands of years ago) that are to blame!

        (I have no idea what the author meant by "the herpes virus (HHV-6)": HHV-6 causes roseola, a childhood disease even more universal than chickenpox; it's sometimes embedded in the human genome, but is not a retrovirus. We don't know what happens if you catch HHV-6 as an adult because it's never happened.)

        • vordark says:

          The rule of thumb for schizophrenia is that one third of patients, without treatment, will continue exhibiting psychotic symptoms for the rest of their lives; one third will get better after the initial episode, but eventually redevelop symptoms; and one third will have a single episode and live out the rest of their lives without symptoms. It's not true that you're stuck with it for life.

          This is not entirely accurate. There is no "rule of thumb" here, partly because there is no universally accepted definition of "recovery" for patients with schizophrenia, and partly because nearly all of the offered definitions allow for some symptoms persisting.

          I can also tell you from personal experience that even if you aren't symptomatic on any given day, week, month, whatever, you *are* still stuck with it.

        • left by says:

          You may not have heard, but we actually have a vaccine for chickenpox (VZV), and we give it to kids, and it works (they don't get chickenpox, at least as much as they don't get the various other diseases we vaccinate for). It's a toss-up public health decision, so where you live they might not vaccinate, despite having sufficient funds, because someone made a call and decided the increased risk of shingles (from reduced re-exposure) during the ramp-up period (ie one human lifetime) was a bad trade. But if you care the vaccine is licensed, so you can get it done privately.

          • mentallill says:

            Thanks! Yeah, that's pre-1995 information (I assumed the original poster was born before 1989 or whatever, but that only shows I'm old). It's still a good example of what a relatively benign herpes virus looks like: you never clear the infection, but it also doesn't kill you, and it's a bad idea to keep children away from the virus entirely - vaccinating everyone is ideal, of course, and I fully agree that parents should ask for (or ask about, at least) vaccination for their children even where it's not routinely recommended: you're trading off someone else's case of shingles against a health risk for your kid (it's only apt that you might have to pay to opt out of chickenpox communism - it's best to think of vaccination decisions as a kind of fun game in which Obama Death Panels try to save money by convincing your doctor not to give you every single vaccination jab they can think of, and your job is to trick them into leaving you alone in the examination room and injecting yourself/your kid with everything there).

            I personally have had chickenpox before a vaccine was available, but can't really recommend the experience. Service was lousy as I wasn't the only sick child in the house, and it was seriously itchy. Get the vaccine and do anthrax or snakebite or something that gets you life-long sympathy - and symptoms you can safely exaggerate because your parents have never had it.

            • left by says:

              It's not about money, as I thought I made clear. This is the same mistake people make with cancer screening programmes. Ignoring the financial costs (not that bureaucrats are entirely able to do that, but anyway) there is a health trade off being made. It's always a trade off, you are never getting something for free. Worse, there is no "safe default". If you take no decision the people won't "make the decision themselves" as free market fanatics would like to imagine, they're too busy.

              Sometimes it's easy. Measles kills and brain damages WAY more children than the vaccine, so giving kids the measles vaccine is a good public health intervention. Sugar pills don't work, tricking patients is unethical, so giving out "homeopathic" vaccines is a bad public health intervention.

              Often it's hard. There's quite a lot of variation in pap smear programmes. This is not because some places hate women more than others and want them to die of cancer. It's because medical scientists are genuinely uncertain about the benefits of different levels of coverage, not sure how much weight to give to one study's results over another. For every woman your programme prevents from getting full blown cancer, some hard-to-determine number will suffer unpleasant and perhaps life-altering interventions. This is not a pin-prick in the arm, it's potentially major surgery with all the risks that entails. Even if we could put a hard figure on it, how many is too many? Five? Five hundred? Fifty thousand?

      • relaxing says:

        Why would you post this.
        You know nothing about the topic.
        The scientists studied the topic for years.
        Why would you post this.

  2. rane500 says:

    Makes me wonder if the chronic (almost monthly!) ear infections I had as a child (bad enough to leave me sobbing in pain some nights) helped make me the medicated loon I am today.

  3. ctd says:

    Ah, truly God's plan for us is beautiful and mysterious. :|