Monday, April 2, 2012

News of the Century: Genes Prove Einstein wrong, change faster than neutrinos!

Why bother arguing whether the speed of a neutrino is faster than the supposed upper limit to speed, that of light?  The measurements are so delicate that nanosecond discrepancies can be very difficult to interpret or, more accurately, a theory so well established (deeply entrenched?) as Einstein's theory of relativity will not be overthrown on such scant evidence.  But don't even bother, because we now have the desired falsification, and surprisingly it comes from genetics!

A new report shows (well, says) that the rate of autism is nearly 80% higher than it was a decade ago. That is rather dramatic, perhaps astonishing if you believe the data are disgnostically accurate rather than that it's due to diagnostic changes or predilections to cause behavioral variation 'autism'.  This is of course disturbing, as it shows some serious issues and that we have a major therapeutic, educational, or other kind of burden to bear to help the affected kids and their families.

But that's only part of the story.  Since our research establishment is so committed to the idea that everything, including how you vote and whether you like to be abused as a child, is genetic, and that autism must, simply must, be seriously genetic, the implications of this change in disease risk are widespread.  Indeed, if this is all true, the presumed genetic basis of autism must have evolved faster than evolution makes possible. Faster than parent-offspring transmission and natural selection!  That implies, believe it or not, non-material transmission of genetic variation and its non-material (in the 'ether' that physicists thought they'd long ago shown doesn't exist) changes in the genes and their frequency, while they are literally disembodied before being reinserted into people before they reproduce.

This disembodied evolution changes things faster than neutrinos fly under the Alps from Switzerland to Italy, and shows that even Einstein's laws are wrong!

When is a trait a trait?
It may seem obvious that an organism has various traits, and these must therefore have a genetic basis and, furthermore, must have evolved by natural selection screening on the traits (and hence molding the underlying genetic basis).  But this is not an accurate way to view the living world.

A human trait like autism illustrates the point.  If we screen more intensely, or set up new diagnostic criteria, or if there are reasons that autistic children qualify for special educational assistance, or we invent new imaging or biochemical measures of brain function that are used to specify a trait, then what is changing is the trait itself!  That's because the trait is to this extent in our minds, not inherently in the individuals.  Autism today is not autism yesterday.

In that case, the genetic basis will change and no neutrinos need be involved.  Because if we categorize or measure something differently, there is every reason to expect it has a different underlying genetic architecture.  Eyes are made by different genes than fingers, but if we re-name 'eyes' in a way that includes what used to be called fingers, we have to expect genetic associations to change.  Likewise if we rename what 'autism' is.

Even natural selection doesn't see 'traits' per se, but only is reflected in reproductive success.  We may care about, say, running speeds of rabbits and foxes, but nature 'cares' only about rabbits that escape and foxes that get dinner, and hence live to reproduce.  Running--something we define and measure--may or may not be part of the selection.  But if we choose to study the genetic basis of escape or pursuit speed, we can ask questions about its evolution.  But that's different from knowing that the us-defined trait is what in some trait-specific sense caused an us-defined adaptation, or vice versa.

An alternative explanation
It is, of course, possible that we've misinterpreted and that all that's really happened is something in the environment, including diagnostic definitions and screening intensity or other reasons people may look for, or look more intensely for, autism.  In that case, autism then isn't really the same as autism now, so the principles of materialistic genetics haven't really been violated.  That's less exciting, but more likely....and raises an important principle.

So why the insistence on intense genetic approaches?
One can ask why we keep pouring money into genetic studies like GWAS and related high-throughput but hypothesis-free 'omics' approaches.  One answer often given by geneticists is that they are, after all, geneticists and that's what they do.  Another favorite of epidemiologists is that once we identify the genes, we can treat them as fixed risk factors and correct for them (statistically) in searching for the important causes, which are environmental.  Whether you find these explanations adequate or think there may be other motivation behind them is your diagnosis.

But one defense of genetics over everything else is that when something changes faster than a speeding neutrino, it must be because there are common underlying variants with large response effects to the environmental changes.  So if we identify those genes we can....remove the environmental trigger so we don't have to identify those genes.  But a lot of experience and intense studies suggest this is just not the case, and is more wishful thinking or scientific momentum-preserving.

Normal traits like stature, obesity, and blood pressure that aren't diseases, as well as many complex diseases like diabetes, and hypertension, and asthma and numerous others have risen in frequency very rapidly during past decades.  They should have these same characteristics of common-variants responding in a big way to rapid, major environmental change, if that explanation is correct. These traits have been GWAS'ed to death, so to speak, and not only do we have the hyped-up issue of 'hidden heritability' (family risk not identified by GWAS studies), but we also clearly find that a few common variants with big effects simply do not explain these diseases.  So applying this it-must-be-major-genes argument to autism is questionable to say the least.

Genetic variation responding to environmental change is always a factor, but there is no reason whatever to think genetics will contribute much to the overall problem.  Genetics is most likely to contribute to those cases of autism--and they exist--for which a specific high-risk genetic variant has been identified.

What to do about a major societal problem, a real problem, like autism is less clear. But just plowing ahead isn't necessarily the most societally responsible approach.

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