Thursday, June 30, 2005

MSG - Not as toxic as the people who claim it is.

On a recent surfing trip through the Internet, I discovered that I was not one of the people listed by the ironically named "Truth in Labeling" website as denying their outrageous and melodramatic claims about monosodium glutamate. Imagine my shame and humiliation! Well, consider this to be the electronic equivalent of throwing down the gauntlet - if they don't list me within one week, I challenge them to a duel of wits. I don't care if it is unsporting to fight an unarmed opponent - they have given me grave offense!

Folks, let's try to inject a little reason into these poor deluded souls - I might suggest using the large veterinary syringes, since their reason deficit appears to be extreme. Monosodium glutamate (MSG) is simply the sodium salt of glutamic acid - a very common amino acid.

Immediately upon ingestion - literally as soon as it hits your saliva - it dissociates into glutamate (the ionized form of glutamic acid) and sodium (a component of table salt). Thinking that this causes neurological disorders, obesity (unrelated to simply stuffing too much food into your pie-hole) and other mysterious ailments is madness. And I mean that in a caring way.

If you eat anything containing protein, your own stomach acids and proteolytic enzymes will liberate large quantities of glutamate, much of which will become ionized upon reaching the alkaline environment of your duodenum (assuming that your pancreas is working). The only difference between getting a load of MSG in your soup and getting a load of glutamate from your steak is in the timing. MSG provides glutamate in a "pre-digested" form, which may explain the people who experience a headache from eating foods with MSG.

However, apart from headaches (and the data is still not rock-solid on that), no other health problems can be laid at the (metaphorical) feet of MSG. If the folks at "Truth in Labeling" or "MSG Myth" (another unintentionally ironic title) had any data to support their claims, they would have more than assertions, anecdotes and wild, unsubstantiated conspiracy "theories" on their websites. Seriously, these folks are worse than the thimerosal-causes-autism crowd.

There. That should be enough to get me my rightful place on the MSG "wall of shame."


Wednesday, June 29, 2005

When is an epidemic not an epidemic? When it's an artifact!

A recent media release from the journal Pediatrics announces an article that promises to turn the whole "autism epidemic" issue on its head:

"Is autism really on the rise? A new study entitled, "U.S. Department of Education Data (USDE) on 'Autism' Are Not Reliable for Tracking Autism Prevalence" says that the data that many autism advocacy groups are using to show a rapid increase in autism may not be accurate. The author of the study analyzed the USDE data and found that the results strongly conflict with the findings of several other autism prevalence studies.

The USDE data suggests that there are as many children who are newly diagnosed as autistic at 15 years of age as there are at eight years of age. In contrast, four recent studies suggest that the majority of diagnoses are made before age eight. Another inconsistency in the USDE data is that it seems to show a break in the rise of autism prevalence between age 11 and 12. This is actually the time in which milder cases of autism are most likely discovered due to the change of moving from the structured environment of elementary school to the more self-directed environment of middle school.

The author says the USDE's data problems are due to the fact that the school districts' criteria for identification were inconsistent. The school districts were the source of data for the USDE."

Since many of the anti-vaccination weirdos and autism-dogmatists use the USDE data to support their increasingly flimsy claims, this article should ignite a real firestorm of protest. Fortunately, protest and unbottled angst will not change the facts.

Let the games begin!


Friday, June 24, 2005

Genetics 102: "Autism ain't a genetic disease!" - Not!

After posting my commentary on the rather appalling state of genetics education among senior editors of major news organizations (see here), I received an e-mail in which the author roundly castigated me for implying that autism might be a genetic disease. Well, for starters, I am not implying that autism is a genetic disease, I'm coming right out and asserting that it is.

Proponents of the myriad autism causation hypotheses - mercury, vaccines, gluten, casein, plasticizers, etc. - all insist that exposure to these substances cause autism in a subset of children. None of them has said (or even implied) that any of these substances causes autism in every child who is exposed to them. The reason they don't (and can't) say that is that it would be painfully easy to refute such a claim. It is obvious that the majority of children exposed to these substances do not develop autism - since even the highest estimates of autism prevalence can only claim that a third of a percent of children are autistic. This leaves 99.7% of children - most of whom have the same exposures as the autistic children - who are not autistic.

So, how do we explain how exposure to a substance (be it a chemical, a virus or a protein) can cause no illness in most people and yet cause illness in a few? Well, the answer to that problem is genetic variation. How is it that a small percentage of people exposed to Coxsackie virus B4 develop diabetes and most people do not? Genetic variation. How is it that, in the pre-antibiotic days, Plague was not 100% fatal? Genetic variation. How is it that some groups of people are prone to breast cancer and others are prone to gastric cancer? Genetic variation.

As unpalatable as it may be to some of the autism advocates, any claim that exposure to a substance causes autism has to explain how that exposure doesn't cause autism in 100% of children exposed to it - and the answer is... genetics.

Personally, I'm fine with the idea that there are a group of children who are genetically susceptible to develop autism after exposure to some substance or another. This would be completely in line with many other disorders. In fact, it could probably be argued (and successfully) that all disease is the result of some aspect of the genome. You could even make an argument that certain accidental and traumatic injuries are the result of risk-taking behavior that might also be encoded in the genes.

So, as painful and uncharitable as it may seem, autism is - in all probability - a genetic disease. Like so many others. To deny this is to take yet another step away from reason and toward...the Dark Side.


Thursday, June 23, 2005

Homeopathy in Perspective

In today's spam serving, along with the offers to make my breasts larger and penis bigger was an offer for homeopathic growth hormone. This miracle of modern medicine, so the advertisement says, will make me feel younger, give me more energy, "supercharge" my sex drive (should go well with the larger breasts and penis) and cause all sorts of vaguely worded benefits to come my way. They didn't promise me the winning numbers in the Powerball Lottery, but I thought that it might have been implied.

Being the scientific curmudgeon that I am, I thought that a few minutes with a calculator might be in order. The advertised elixer of youth claimed to be a 40C homeopathic dilution, which meant that the original human growth hormone solution had undergone 40 consecutive 100-fold dilutions (take one volume, dilute it to 100 volumes). This is equivalent to a dilution of one volume to 10^80 (10 to the 80th power) volumes - that's a one (1) with 80 zeros following it (to the left of the decimal place). For those who aren't up on their math, that's a REALLY big number.

Let's try and put that in perspective, shall we? To make this dilution of human growth hormone, you would need to take one molecule of growth hormone and drop it into just over 3.5 X 10^53 liters (or kilograms) of water.

How much water is that, I hear you ask? Well, the entire mass of the solar system is only a shade over 2 X 10^30 kilograms, and the high estimate for the mass of the Milky Way galaxy (that's the one we're in) is about 2 X 10^42 kilograms, so this would be roughly the mass of 100 billion galaxies the size of the ours. That's a lot of water! [Note: that much water, if it were collected in one place, would result in the formation of a black hole large enough to collapse the entire Universe - you might want to stand back a bit.]

Remember now, that this vast amount of water still only contains one molecule of growth hormone. Finding a needle in a haystack is infinitely easier that finding that one molecule in all that water. Fortunately, the homeopathic "doctors" tell us that it doesn't matter that our chance of getting a vial or pill with that one molecule of growth hormone is less than our chance of winning the Powerball Lottery....ten times in a row. No, it turns out that water has a "memory" of the growth hormone that was "imprinted" on it by the shaking process that accompanies each dilution.

If anyone thinks I'm pulling their leg, I'm not - at least, I'm not kidding that fully grown adults not currently adjudged insane assert that these crazy stories are true. Personally, I think the "memory of water" thing has some giant holes.

Let's get right past the whole problem of physics and the fluid nature of water and its inability to hold a coherent structure for anything like the amount of time it takes me to read the label on the bottle - with my reading glasses. That alone should be enough to stop the homeopaths, but it doesn't. How about if we take them at their word and agree, for just a minute or two, that water can "remember" things that were in it when it was shaken. What would be the logical consequences of that?

Well, if water can "remember" things that were in it when it was agitated, why doesn't it "remember" the millions of fish that were in it when it spilled over rocks, waterfalls and dam spillways? Am I taking 500C fish slime with my 40C growth hormone? Remember, too, that in the upside-down world of homeopathy, greater dilutions have greater power. So, when I drink tap water, I should be experiencing the opposite of what happens to me when I am exposed to raw fish.......I'm not sure I like where this is going.

The fact is that the proponents of homeopathy have painted themselves into a corner. As long as they simply said "It works, we don't know how.", they were on fairly safe ground. Their claims still had no scientific merit, but they didn't give the real scientists an edge to pry against. Now that they have invested in this "memory of water" fantasy, trying to make it into a "science", they are out from under their rock and scurrying in the daylight.

I hold to no hope that the vast legions of the inilluminati are going to be at all persuaded by my little exercise. Ignorance is still the chief religion of the masses - as it has been since the dawn of time. However, if this can put a little sand in the gears, can cause one person wavering on the edge of the abyss to pull back, then it was worth all the time and effort.


Wednesday, June 22, 2005

Genetics 101: "The Amish Anomaly"

Dan Olmsted, senior editor at UPI, has found the cause of autism by looking for it among the Amish people of Lancaster County, Pennsylvania. He claims that, because he couldn't find enough autistic people among the Amish, autism must be due to something that the general population does that the Amish do not. Skipping over SUV's, computers, cellphones, jet airliners and television as possible causes, Mr. Olmsted instinctively homed in on the one "true" cause: vaccines!

Expecting to find 1 in 166 Amish people to be autistic (probably from US Department of Education data, but no source cited), he could only find one. This child, a girl adopted from China, had been (gasp!) vaccinated. This, apparently, was enough of a smoking gun for Mr. Olmsted to indict the mercury in vaccines as the cause of autism (see also), since the Amish generally don't vaccinate their children.

The obvious first question is how accurate Mr. Olmsted's "epidemiological survey" might have been. The Amish are not known to be an extroverted group who welcome intrusive investigative reporters into their homes and tell them the intimate details of their families. It is entirely possible that Mr. Olmsted may have missed a few autistic people. But leaving aside the question of accuracy, is it possible that this "anomaly" of apparent low autism rates among the Amish might have another explanation?

There is another equally plausible (some might even say more plausible) explanation - one that Mr. Olmsted has apparently dismissed, since he had it right in his hands. The Amish, and their neighbors the Mennonites, have been studied by geneticists for some time because they are a genetically isolated community. Although they accept converts, they don't get very many and so they don't get much "new blood" (genes). In addition, they don't move around much and their members tend to marry within the community - those who don't often leave and join their "English" (as they call people outside their communities, regardless of ethnicity) spouse outside of the community.

In genetic terms, what is happening is called "inbreeding" - and it has some very predictable results. One of these is that some variations of genes are lost and other variations become more common. There is a tendency to genetic uniformity, with only a few of the possible variations remaining. Among the Amish and Mennonites, the result has been a dramatic rise in genetic disorders that are more rare in the general population (see here, here and here) as a result of this rise in frequency of the "abnormal" variations of several genes.

Although inbreeding has a generally bad reputation (think Romanov's) because of the rise in genetic disorders, it can also lead (with equal likelihood) to the loss of genes for "bad" things, like autism. So, it seems only fair that, with their increased prevalence of so many genetic disorders, the Amish might have gotten a bit of luck and lost the gene for autism. Of course, this sort of thing doesn't make good UPI articles, and so apparently got flushed with the rest of the rational science that Mr. Olmsted managed to dig up.

Now, I have made this argument before and gotten the response, "Do you really think that the Amish have different genes than we do?" No, I don't, but that question exposes the ignorance of the speaker. All humans, with a few exceptions due to chromosomal deletions or duplications, have the same genes. It is the different variations of these genes - called alleles - that make us all unique individuals (except, of course, for indentical twins, who have the same alleles - sorry, folks).

It is quite reasonable to assume that the Amish have different alleles (more precisely, different allele frequencies) than the general population because they are pretty much genetically isolated from the rest of us. The genetic work done on the Amish and Mennonites confirms this - the only stretch is assuming that this difference will have no effect on the prevalence of a certain disorder, namely autism.


Monday, June 20, 2005

...And over-reaching, they fell flat on their faces

As this blog opens, Senator Durbin of Illinois is still standing by his comments in which he compared the treatment of prisoners in Guantanamo Bay ("Gitmo" to the press and Marines) to treatment of prisoners by the Nazis or by the Soviets in the Gulags or the homicidal regime of Pol Pot. In trying - I assume, perhaps naively - to condemn the mistreatment of prisoners by US troops, he has fallen into the same hole as Amnesty International by overstating an argument that would have done fine on its own.

Maltreatment of prisoners is a "bad thing" for a number of reasons:

[1] It's just plain "bad" to mistreat people who are at your mercy. You know, the "ethics" and "morals" thing.

[2] Mistreating prisoners does not actually make them more willing to talk. In fact, even hard-core physical torture has been shown to be counterproductive to interrogation - people being tortured (and, by extension, mistreated) will say anything they think will get the torment to stop. Not necessarily the truth, but what they think their captors want to hear. This does not lead to "good intelligence".

[3] Even the Nazi SS troopers found that torturing (and killing) helpless people takes a toll on the psyche of the people involved. People who have been involved in torture (and, by extension, mistreatment) often become less effective at their other jobs and in interpersonal relationships.

[4] Having a reputation for humane treatment of prisoners makes the enemy combatants more willing to surrender. A reputation for harsh or cruel treatment leads soldiers to "fight to the death".

[5] No matter how manifestly unfair it may seem that we have to be the "good guys" while the other side gets to blow up children, behead reconstruction workers and assassinate doctors and nurses, it's the side we chose to be on.

These are all very good, cohoerent arguments against mistreatment and torture and you'll notice that none of them involved comparisons with Nazis, Soviet Gulags or Pol Pot. This is actually a good thing, since the prison camps at Abu Graib and Guantanamo Bay don't really compare.

The Nazis killed over 9 million people in their prison camps - mostly Jews, but a number of other ethnic groups as well. The Soviets - under Stalin alone - killed over 3 million of their own citizens in the Gulags. Pol Pot, not as good a record-keeper as the Nazis or Soviets, killed between 1 and 3 million people. As you can see, Abu Graib and Guantanamo Bay aren't in that league at all. And that is exactly what people are going to say in order to redirect attention away from what is happening and onto the people (e.g. Senator Durbin) and groups (e.g. Amnesty International) who are overstating their position.

The problem with trying to over-reach your position is that you stand a good chance of falling on your face.