Sep 16 2014

The Genetics of the Schizophrenias

A new study sheds further light on the genetic basis of the group of psychiatric disorders known collectively as schizophrenia. Further, the study (actually a collection of four studies) takes a new approach that might prove generally useful in associating genetic variation with disease risk, even beyond psychiatry.

Schizophrenia

In popular culture the term “schizophrenic” is often used to mean split personality or multiple personality, but this has never been the actual definition of the term. I’m not sure what the origin of this misconception is. The word “schizophrenia” does mean “split mind” but refers to mental illness characterized by disordered or delusional thinking. The “split” is between reality and mental function.

For at least several decades it has been clear that schizophrenia is not one discrete disorder, but rather it is a set of similar disorders. Symptoms include hallucinations, delusions (persistent false beliefs that do not have a cultural cause), impaired reality testing, bizarre thoughts and behaviors, often but not always paranoid in nature, a disconnection between thoughts and emotions, and lack of motivation or activity.

Part of the challenge of studying schizophrenia is that it is a clinically defined set of disorders, meaning that the category is based upon the signs and symptoms displayed, not any knowledge about underlying cause or biology. The brain, as you might suspect, is an incredibly complex organ with many interacting parts, and so there is likely to be a complex relationship between the underlying mechanisms of schizophrenia and the clinical manifestations.

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Sep 15 2014

Stem Cell Transplant First

NeurologicaBlog is very meta. I like to not only communicate science, but explore how best to communicate science, including thinking about how to communicate the need to think about thinking. (Cue the endless meta-regression.)

For example, there is often much to criticize about how science news is reported in the general media. Part of the problem is that science mostly advances by accumulating baby steps.  Baby steps, however, don’t always make for compelling headlines, and so every advance becomes a “breakthrough,” every mystery has scientists “baffled,” and every study may some day lead to the cure for cancer, rid us of the common cold, or produce a piece of technology similar to that found in popular science fiction.

Part of the challenge of being a skeptical science communicator is to convey simultaneously the deserved awe of cool science, including the potential implications of genuine advances, while also discussing the need for caution in interpreting results, and essentially throwing a wet blanket on premature hype. It can be a delicate balancing act.

I had all this in mind when I approached the main topic of today’s post – a rather exciting and anticipated advance in stem-cell technology. Japanese researchers have created a sheet of retinal epithelial cells from a patient’s own skin cells. First they had to induce pulripotency on the skin cells, which essentially turns them into stem cells (iPS cells). Then they had to coax these created stem cells into becoming the desired cell type which in this case is retinal epithelial cells.

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Sep 12 2014

Features of Denialism

Denialism is a thing. What I mean is that denialism is a definable intellectual strategy, with consistent features that tend to cluster together. I first wrote about denialism 12 years ago, before global warming denial made the term more widespread. I pointed out that certain beliefs tend to follow the same fallacious arguments – HIV denial, creationism (evolution denial), holocaust denial, and mental illness denial. I would add now global warming denial and germ theory/vaccine science denial.

I characterized denialism as a subset of pseudoscience, one that tries to cloak itself in the language of skepticism while eschewing the actual process of scientific skepticism. But further, denialism exists on a spectrum with skepticism, without a clear demarcation in between (similar to science and pseudoscience). People also tend to use themselves for calibration – anyone more skeptical than you is a denier, and anyone less skeptical than you is a true believer.

Geneticist Sean B. Carroll (not to be confused with the physicist Sean M. Carroll) in his 2007 book, The Making of the Fittest: DNA and the Ultimate Forensic Record of Evolution, lists what he identified as the six core features of denialism. I think they make an excellent list, and would like to expand on them:

1) Cast doubt on the science.
2) Question the scientists’ motives and integrity.
3) Magnify any disagreements among the scientists; cite gadflies as authorities.
4) Exaggerate the potential for harm from the science.
5) Appeal to the importance of personal freedom.
6) Object that acceptance of the science would repudiate some key philosophy.

As you will see, all of these strategies are insidious because they are extreme versions of reasonable positions. Their underlying principles are sound, it is their specific application that is the problem.

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Sep 11 2014

19 Years of Feeding Animals GMO Shows No Harm

Often GMO critics will argue that the biotech industry is conducting a massive experiment with our food supply by introducing genetically modified organisms. The implication is that GMOs are not adequately studied, which is at best debatable, but in a way they are correct. We can look at what has happened in the 19 years of GMO use starting in 1996 to see if there have been any adverse effects.  A newly published study, Prevalence and impacts of genetically engineered feedstuffs on livestock populations, does just that. (Full study, may be behind a paywall.)

The study authors, Van Eenennaam and Young, first review the existing literature on animal feeding studies. They then review available data on livestock outcomes to see what effect feeding them mostly GMO since 1996 has had, if any.

GMO Feeding Studies

The first regulatory hurdle for safety testing of GMOs is to establish “substantial equivalence.” Researchers must show that the genetically engineered crop is essentially the same as the parent variety in all ways except for the desired introduced genetic change. The authors report:

Over the past 20 yr, the U.S. FDA found all of the 148 GE transformation events that they evaluated to be substantially equivalent to their conventional counterparts, as have Japanese regulators for 189 submissions.

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Sep 09 2014

Has Jack the Ripper Finally Been Solved?

Jack the Ripper is perhaps the most iconic serial killer in history. Part of the mystique of this dark figure is the fact that he was never identified, leaving room for endless sleuthing and speculation. Every Ripper fan has their list of favorite suspects, usually filled with famous and powerful people of the time to add even more interest. My favorite, of course, is that he was a time-traveling friend of H. G. Wells.

Now a private researcher, Russell Edwards, claims that he has finally solved the case. First I will present his story without comment, and then we can take a skeptical look at it.

Edwards claims he acquired a blood-stained shawl in 2007 that is supposed to be from Catherine Eddowes, one of the five fairly accepted victims of the Ripper. The shawl was apparently recovered from the scene of Eddowes murder, and was covered in her blood. Acting Sergeant Amos Simpson took the shawl home as a gift for his wife. She was, apparently, not impressed and stored the shawl away without cleaning it.

The shawl remained in the possession of his family until they auctioned it off in 2007 and Edwards acquired it.

Edwards then solicited the help of Dr. Jari Louhelainen, a Finnish expert in historic DNA. Louhelainen found that the 126 year old shawl contained a great deal of blood, likely all from the victim. However, he also found a semen stain on the shawl. Genomic DNA is unlikely to have survived 126 years sufficiently intact for DNA matching. However, mitochondrial DNA is more hardy and likely did survive.

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Sep 08 2014

Internet Echochambers

I recently came across a post on the skeptic subreddit pointing to the rules of the 9/11 truther subreddit:

Welcome to 911truth! The purpose of this subreddit is to present and discuss evidence showing that the US Government’s version of the events of 9/11 cannot possibly be true. Submissions or comments supporting the official version, including links to sites purporting to “debunk” the 9/11 Truth Movement (depending on context), are considered off-topic here.

Rules:

  1. Stay on topic. Off topic comments are subject to removal.

Rule #7 also made me smile:

7. No caps lock.

This is the double-edged sword of the internet – it allows for unprecedented on-demand access to incredible information, but that information is biased.

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Sep 05 2014

Ashya King and Proton Beam Therapy

These cases are always heart-breaking and difficult to write about, but many people have been asking me about the Ashya King case and there are are few points worth exploring.

For background, Ashya King is a 5-year old boy living with his parents in the UK. He has a type of primary brain tumor called a medulloblastoma. This is the most common type of malignant brain tumor in children, and typically is located in the back of the brain, in what is called the posterior fossa.

His parents, who are understandably concerned and want the best treatment for their son, would like him to receive a new type of therapy called proton beam therapy. His UK doctors do not feel this specific treatment is indicated. In desperation, Ashya’s parents removed him from his UK hospital and drove him to their vacation home in Spain. Their plan was to obtain proton beam therapy in Spain.

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Sep 04 2014

Doubt and Confusion over Global Warming

Global warming (or global climate change) continues to be a contentious issue because of the political ramifications of the science. When I talk to those who doubt human-caused (anthropogenic) global warming inevitably they express a strong political opinion about the implications of AGW – that it is being used to justify government take-over of private industry.

There are also those on the left who embrace AGW as a way of reinforcing their ideological economic opinions. None of this makes AGW correct or mistaken. The political implications of AGW are irrelevant to the science.

I might be tempted to say that the controversy over AGW is partly being driven by the fact that the science is very abstract. There is a ton of data that can be used to support just about any opinion you wish to defend, if you are willing to cherry pick. The data is also somewhat abstract and is very complex.

While I do think it’s true that the nature of the data regarding AGW does exacerbate the controversy, I can’t say it is a necessary component, as there are controversies surrounding far simpler rock solid science, such as the efficacy of vaccines.

In any case, AGW does have a particular challenge in that the discussion is very statistical and graph heavy, two things which are easy to manipulate and sow confusion.

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Sep 02 2014

Witch Hunter Sues BHA

The British Humanist Association has announced that they are being sued by notorious Nigerian “witch hunter”, Helen Ukpabio, for half a billion pounds for alleged libel. The only reasonable response to this situation, in my opinion, is to magnify the criticism of Ukpabio as much as possible.

For those who are not aware, I am also being sued for expressing my critical opinions. You can read the full details here. I have always supported my fellow skeptics in the past when they faced being silenced through legal intimidation, but now I have to disclose that I have a personal connection to this issue as well.

In any case – Ukpabio, in my opinion, represents an extreme version of the harms that result from abject superstition. She considers herself (or at least claims to) a “Lady Apostle” and makes a career out of exorcising children she believes are possessed by spirits.

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Aug 28 2014

Bt and Leukemia – Another Anti-GMO Myth

The headline of an article on the Organic Consumers Association proclaims, “New Study Links GMO Food To Leukemia.” The same article trumpets the thoroughly discredited Seralini study. The claim is not true, but is part of a pattern of behavior that is depressingly familiar.

The pattern is not unique to anti-GMO activism. In fact, it seems to be the default human behavior. We tend to search for information that supports our currently held views. The more passionate we are about those views, the more industrious we are in finding apparent support, even if it means twisting and distorting information.

I find myself doing this all the time – if a study or new piece of information directly opposes something I currently believe, then my mind immediately starts finding reasons to dismiss the information. I have the opposite reaction when the information confirms my current beliefs, I find reasons to accept it.

But then I consciously step back and try to take an objective look at the information. This is not always easy, and may involve specialized knowledge I don’t have. I then have to look to experts to see if there is a clear consensus opinion. In other words, I don’t just stick with my knee-jerk reaction to information. I go through a process of evaluation and critical analysis. My goal is to come to a valid conclusion, one that will hold up under critical assault, whatever that conclusion is. Meanwhile I have to remain open to the possibility that my conclusion is wrong or incomplete, that I missed something or made an error in my process.

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