It’s time to get past the idea that autism is genetics

19 Feb

Or, at least, this is what David Kirby has to say in a recent interview.

Yes, I’m tired of David Kirby too. But some statements are just plain silly.

“I don’t believe autism is genetics,” he said. “I wish we could just get past that argument and accept the fact that these kids have been hit with some environmental trigger of some sort, or sorts, combined with these genetic predispositions … and get on with it.”

Here’s an admittedly sarcastic response: I am so glad when outsiders to the autism community spend years promoting an agenda that attempts to take focus away from needed science.

And, yes, I noticed that to David Kirby it is still all about “these kids”. Adults just don’t register on his radar.

Mr. Kirby is not always consistent. In the past he has stated:

I have always said there may be a small percentage of people with autism spectrum disorder (perhaps those with Asperger Syndrome) whose symptoms are a result only of their genetic makeup, with no environmental factors involved at all.

So, “a small percentage” in his view, can now be forgotten as we “get on with it”.

I wish Mr. Kirby well with his new book. I hope for the sake of the people whose lives he will affect, he has learned from the damage he caused to the autism communities.

26 Responses to “It’s time to get past the idea that autism is genetics”

  1. Colin Jenkins February 19, 2010 at 08:04 #

    This headline was the first thing I read after waking up early and for some reason I read “past” as ‘through’ – I got all excited and started thinking about who to tell that recent events had started an anti-vax-ideology busting wave – I’ll put my naivety down to the time of day… 🙂 Keep up the good work.

  2. reasonablehank February 19, 2010 at 08:55 #

    David Kirby…naughty doggy…put down the bone…

  3. Clay February 19, 2010 at 10:25 #

    As long as we’re guessing, my guess is that the “small percentage” is 90 – 95 percent.

  4. David N. Brown February 19, 2010 at 10:38 #

    Shouldn’t it be “autism is genetic”? At first glance, I wondered if the headline was a joke…

  5. chaoticidealism February 19, 2010 at 11:45 #

    I could see the point if he was urging people to find out how the genetics interacted with the environment. That, at least, is sensible, even if I disagree with it. But ignore genetics when twin studies come up with numbers in the 90s? Whatever he’s smoking, I want some.

  6. asha February 19, 2010 at 13:51 #

    Can you pls tell me f autism can be cured using BIOTECHNOLOGY..i have been finding for it 4m past few days..not able to find..f yes,how can it be..

  7. Laurentius Rex February 19, 2010 at 13:54 #

    I do not believe that autism is genetic, in any more than the same sence that everything else is genetic. I’ll give a little example, most people survive in sunlight, some do not, they have a genetic predisposition to harm from what is a vital component of the environment to everybody else. Doesn’t mean we should prevent the sun from shining to protect the few, we have to protect the few by other and more appropriate means.

    The jury is still out in my opinion as to whether there is even an autism that is nosologically seperate from so many other conditions it blends into and crosses over at the edges. More so than ever now, with the sacred Triad being blasted away at.

    Thing is just because I don’t believe there is one unitary condition, disorder call it what you will depending on where you come from, it doesn’t follow that I subscribe to any of the whacko causation theries either.

    Autism is an enigma, it’s a congitive style with multiple developmental outcomes, and no homogenous etiology, so I do applaud those who diligently pick away at it’s edges with a proper scientific endeavour which must be ethically informed.

    The rest however can just go to the perdition of Sartre’s ‘huis clos’ (go google), that is to say the hell that is other people, perpetually locked into opposition, which the blogosphere has become with respect to Autism.

    I have almost given up on people ever understanding my perspective, and where it is grounded. Once the blinkers are on, the fists just fly wildly in any direction.

  8. Joeymom February 19, 2010 at 14:09 #

    Asha: No. There is no cure for autism by any means. However, there are lots of helpful therapies, such as behavioral therapy, occupational therapy, physical therapy, and speech therapy.

  9. Ali February 19, 2010 at 16:09 #

    Laurentius Rex, I agree with you that autism is a thinking style, a developmental difference with multiple outcomes and almost certainly multiple etiologies. I just don’t understand why you would start your comment saying that “I do not believe that autism is genetic, in any more than the same sence that everything else is genetic.” That just seems tautological. Forgive me if I’m misunderstanduing, but you seem to be making the argument that of course it is genetic, because humans have the genes for a wide variety of cognitive styles, so therefore calling it genetic is useless. Could you please elaborate?

    If what you mean by that is that multiple genes and flavours of those genes are involved and that a threshold of these activated presents as an ASD, but that the combination could be any wide variety, then I think we agree.

  10. Joseph February 19, 2010 at 17:07 #

    Wikipedia explains that the model for phenotype is:

    genotype + environment + random-variation –> phenotype

    The “random variation” part is chaos, basically. Most people seem to be under the impression that the model is simply:

    genotype + environment –> phenotype

    To take an example, neurofibromatosis is entirely genetic. It is known exactly which genes cause it. Yet, the phenotype is not really predictable. I suppose it depends on the location of the tumors, and this is basically random.

  11. brian February 19, 2010 at 17:37 #

    An article in the current issue of Nature provides important information regarding why phenotype is not “really predictable”: the differences observed in genetically “identical” organisms [think nonconcordant monozygotic twins] aren’t necessarily due to the environment.

    “ . . . [E]ven genetically identical organisms in homogeneous environments vary, indicating that randomness in developmental processes such as gene expression may also generate diversity.”

    http://www.nature.com/nature/journal/v463/n7283/abs/nature08781.html

    This observed random variation in gene expression of genetically-identical organisms raised in the same environment very clearly refutes the canard that ASD differences in “identical twins” must be due to some environmental factor—it’s clear that some of that difference may be ascribed to environmental effects, but some variation is due to what Joseph termed “chaos”. Such changes do not necessarily imply a continuous gradient: In the study cited, such random variation “is subjected to a threshold, producing an ON/OFF expression pattern of [a] master regulatory gene . . . .”

  12. daedalus2u February 19, 2010 at 17:41 #

    Autism is the property of a phenotype, not a genotype. Some teratogens cause autism. Those teratogens do not change the genotype, they change the phenotype by changing the path of development.

    There are identical twins that are discordant for autism. Identical twins started out as a single fertilized egg. They started out as one genome. The path of development of that single genome as it divided into two, and became two individuals was not “identical” in the two cases, so the two identical twins do not have exactly identical phenotypes.

    I really wish people wouldn’t listen to Kirby. It is clear that he is no scientist, all he cares about is furthering his agenda and making money off the autism community. More than anyone else, he has set back autism research with his inflammatory and wrong shouting of “fire!” in the crowded theater that the stakeholders in the autism community comprise, people with autism and the friends and family of people with autism.

    He does blame vaccines, with no scientific basis what so ever. He blamed mercury with no scientific basis. Now, he won’t even admit that he was wrong to blame mercury.

    He isn’t a scientist, his writing isn’t based on a scientific understanding of anything. His writing is just marketing for the anti-vaxers. Cynical inflammatory diatribes by someone who doesn’t understand what he is talking about, but knows how to inflame the passions of his fellow Ignorati.

    http://www.urbandictionary.com/define.php?term=Ignorati

  13. passionlessDrone February 19, 2010 at 19:49 #

    Hi brian –

    [E]ven genetically identical organisms in homogeneous environments vary, indicating that randomness in developmental processes such as gene expression may also generate diversity.

    Interesting stuff. Have you read the entire paper? Just the abstract is hurting my head, but here are my thoughts anyways.

    Did they give any information as to what was causing the differential expression of the redundant gene, that eventually cascaded to lead to phenotypic differences? This is likely a comprehension problem on my end; but isn’t there some physical mechanism (i.e., chromatin, other genes) that invokes the different gene expression? Is the argument that the application of whatever mechanism(s) is essentially random, and thus, the results are unpredictable? At what point does our relative inability to measure very subtle environmental differences cause them to be legitmately assigned randomness? [Of course, the environmental agents of sole concern to Mr. Kirby likely wouldn’t fall within this leve of detail.]

    I’m not defending Kirby here by any stretch, but I think part of the problem is that our observations of autism rates, which are the progenitor of a lot of discussions, seem to be anything but random. Give me a two years and I can beat the hell out of a coin flip as to which year had a greater perceived rate of autism.

    – pD

  14. daedalus2u February 19, 2010 at 20:08 #

    PD, I haven’t seen the paper either, but I am pretty sure that they really don’t know. I think that it is tied up in the minutia details of cell processes. When a transcription factor causes the expression of DNA, a number of copies of the protein are made. Whether than number is 49, 50, or 51 copies may or may not make a difference. When you have thousands of proteins being expressed simultaneously in each cell, each expression process won’t be “identical” to each other expression process in each other cell, and those expression processes won’t be identical over time. Over time the two phenotypes will diverge, even though they start out with the identical genotype.

    These are the conditions that lead to the butterfly effect, where a differential cause (the puff of a butterfly’s wing) can lead go macroscopic changes later (a hurricane or not). A change from 49 to 50 copies of a protein might have similar macroscopic changes later.

    This is the usual result when you have multiple coupled non-linear processes. They are very sensitive to initial conditions and become inherently non-predictable after a period of time, just like the weather.

  15. passionlessDrone February 19, 2010 at 20:24 #

    Hello friends –

    I found this nice write up of the paper, here:

    http://promega.wordpress.com/2010/02/19/worms-with-the-guts-to-play-games-of-chance-stochastic-effects-and-binary-output-in-gene-expression/

    I’m still a bit confused, but I think the take home message is that a seemingly random set of upstream gene mutations can have the non obvious effect of turning on or off a downstream gene that has a large resultant impact.

    Daedulus2u – Thank you.

    – pD

  16. brian February 19, 2010 at 20:51 #

    Hi, pD-

    No, I’ve seen only the abstract thus far. I’m intrigued, though, that random differences in gene expression can, as you noted, turn on or off a downstream regulatory gene with signficant impact. (Plus–sarcasm off–some of my best friends work with worms.)

    I’ve had a hard time understanding why anyone would deploy the argument that ASD nonconcordance in monozygotic twin pairs must be due to environmental influence. This is an effective, if incomplete, counterargument.

  17. daedalus2u February 19, 2010 at 22:56 #

    If you include as “environmental”, (as I do) the stochastic buffeting that molecules and cells experience from Brownian motion, then a degree of randomness in phenotype development is “environmental”.

    It isn’t a level of environment that will ever be measurable or controllable, but it isn’t genetic.

  18. dr treg February 19, 2010 at 23:59 #

    “To take an example, neurofibromatosis is entirely genetic. It is known exactly which genes cause it. Yet, the phenotype is not really predictable. I suppose it depends on the location of the tumors, and this is basically random.”

    The immune system`s mast cells in the tumour micro-environment are important re the development of benign or malignant tumours.
    http://cancerres.aacrjournals.org/cgi/content/full/68/24/10358
    i.e. neurofibromatosis is “immuno-genetic” as is being discovered with most neuro-psychiatric diseases.

  19. Prometheus February 20, 2010 at 00:28 #

    So, David Kirby says:

    ““I don’t believe autism is genetics…”

    That’s nice. Since Mr. Kirby is a “free-lance” journalist, not particularly well-versed in science of any sort, let alone genetics and epigenetics, I will accord his “belief” the same weight I would that of the boy who delivers our newspaper.

    Seriously, does Kirby really think that his “belief” that autism is not “genetic” (the statement speaks volumes to his understanding of genetics) means anything? I “believe” that green is a better color than red, which is every bit as Mr. Kirby’s “beliefs” about autism.

    Kirby needs to get over himself.

    Prometheus

  20. RAJ February 20, 2010 at 05:50 #

    “I could see the point if he was urging people to find out how the genetics interacted with the environment. That, at least, is sensible, even if I disagree with it. But ignore genetics when twin studies come up with numbers in the 90s? Whatever he’s smoking, I want some”.

    The Baily et al (1995) British twin study you refer to reported 60% concordance in MZ twins. The 90% figure is when you add in discordant twins who have cognitive and social abnormalities not rising to the level of autism.

    The British twin study is of classical twin design which reports simple concordance rates in MZ twins compared to DZ twins. The classical twin study design assumes an equal prenatal environment. The 60% concordance rate is intriguing since 2/3d’s of MZ twins are monochorionic (same placenta) while 1/3 are dichorionic (seperate placenta). Bohm & Stewart have suggested that concordance might aggregate significantly in monochorionic twins who share the same prenatal environment while dichorionic MZ twins may have concordance rates similar to DZ twins who by definition also develop in seperate placentas.

    The one schizophrenia twin study that segregated concordance rate by placenta type reported a concordance rate of 60% for monochorionic MZ twins but only 10.7 concordance rate in MZ twins who developed in seperate placentas.

    http://www.ncbi.nlm.nih.gov/pubmed/7481567?

    The California Autism Twin Study has closed with 225 twin pairs recruited, the largest population based twin study ever attempted. They are sifting through the data now but they have recorded placenta type where the records are available. If they have managed to have recruited a large enough sample of MZ twin with unambigous placenta data the study may answer the question as to the relative magnitude of the environmental and genetic components in autism.

    Simple concordance rates between MZ and DZ twins can lead to false assumptions. The cause of leprosy is infection after exposure to myobacterium laprae. Twin studies in leprosy have reported the same high concordance rates in MZ twins (60-85%) and the same rapid fallof in concordance rates (5-20%) reported for DZ twins that has been reported in ASD twin studies.

    In discordant twin pairs where the discordant twins have cognitive and social abnormalities not rising to the level of autism can also be explained the placenta status. A study that followed the pregnancy of a series of Guinea Pigs heavily exposed to alcohol and found that the levels of alcohol varied significantly when examining alcohol levels in the placenta of the littermates.

    http://www.ncbi.nlm.nih.gov/pubmed/19127948?

    The Califonia Autism Twin Study may be the most important paper published in more than a decade. No dfferences in concordance rates segregated by placenta type would be the strongest evidence ever published for the concept of autism being geneticaly predetermined since the inference is that the prenatal environment played no role in outcomes. IF the data support Bohm & Stewarts hypothesis it would be the most convincing evidence ever produced that the prenatal environment is, as or more important, than zygosity.

  21. Tom February 20, 2010 at 16:50 #

    There’s always been something fishy about the way RAJ represents leprosy studies but I never took the time to look at the literature. Turns out that there are major susceptibilty loci to leprosy infection. Those twin studies he cites actually provided the inital evidence of a genetic link.

    http://www.nature.com/ng/journal/v27/n4/full/ng0401_439.html

    http://content.nejm.org/cgi/content/abstract/361/27/2609

    Turns out leprosy is a good example of gene/environment interactions. So does RAJ lack understanding or does he purposely misrepresent findings to bend to his “environmental evangelism?” Neither scenario gives his musings much credibility.

  22. Sullivan February 20, 2010 at 17:11 #

    Tom,

    thanks for checking that.

    from the NEJM article

    Results We observed a significant association (P<1.00×10–10) between SNPs in the genes CCDC122, C13orf31, NOD2, TNFSF15, HLA-DR, and RIPK2 and a trend toward an association (P=5.10×10–5) with a SNP in LRRK2. The associations between the SNPs in C13orf31, LRRK2, NOD2, and RIPK2 and multibacillary leprosy were stronger than the associations between these SNPs and paucibacillary leprosy.

    Conclusions Variants of genes in the NOD2-mediated signaling pathway (which regulates the innate immune response) are associated with susceptibility to infection with M. leprae.

    association with p<10^-10?!? Pretty clear association.

  23. RAJ February 20, 2010 at 18:17 #

    “Turns out leprosy is a good example of gene/environment interactions. So does RAJ lack understanding or does he purposely misrepresent findings to bend to his “environmental evangelism?” Neither scenario gives his musings much credibility”.

    I have never stated the ASD or Leprosy is entirely environmental. I have stated that the concept of ASD being genetically predermined has failed the test of science. No gene specific to Autism has ever been identified. Lots of candidate genes, however those candidate genes are also associated with a wide variety of neurodevelopmental and neuropsychiatric, hence no specifity as an autism candidate gene.

    The role of medicine is to identify those environmental insults which are associated with links to disruption of brain development. This has already been accomplished with the development of an effective rubella vaccine, the international ban on the use of Thalidomide in pregnancy and newborn testing for PKU.

    Stop putting words in my mouth that I never stated.

    I’ll ask you one simple question. If the California Autism Twin Study proves that the genetic component of autism has been massively over stated would you accept the results? I would, either way.

  24. Tom February 21, 2010 at 01:05 #

    RAJ, you have spent considerable effort trying to undermine autism genetics.

    You continually challenge all to name one single autism gene and yet here’s a treasure trove: http://gene.sfari.org/ I have posted the link twice before and you have failed to offer any direct response. (I don’t blame you, that’s a lot of published data for a novice to refute.)

    You use leprosy as an example of how daft genetic research is by citing twin studies, but fail to disclose that, somewhat counterintuitively, genetic susceptibility exists in this infectious disease. Pretty big omission, given that you’re trying to claim the opposite. It’s just too damn easy to check the published record and compare it to your misinformation campaign.

    If proper studies find that purely enviromental exposure is a larger culprit than once thought, than I, and all of the scientific community, would accept those findings. Trouble is, you’ve already jumped the gun.

  25. dr treg February 21, 2010 at 23:23 #

    Further evidence that leprosy is immuno-genetic as is being discovered with most diseases.
    http://www.modernmedicine.com/modernmedicine/Pathology/Immune-System-Linked-to-Leprosy-Susceptibility/ArticleNewsFeed/Article/detail/648830

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