For those of you interested in the origin of autism

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There was a show on NOVA this morning, called 'Ghost in your genes'. If you want to watch a summary of it, you can view it here:

http://www.pbs.org/wgbh/nova/sciencenow/3411/02.html

If you want to watch the full episode, it plays several more times during the week. Just go to TVguide.com and look for Nova (it is on the public broadcasting station) The full episode is also on youtube, if your willing to watch it on your computer at these links:

Part 1
http://www.youtube.com/watch?v=8j949RyNXqc
Part 2
http://www.youtube.com/watch?v=NCNXMl4j ... re=related
Part 3
http://www.youtube.com/watch?v=Vw5Faihs ... re=related
Part 4
http://www.youtube.com/watch?v=_6VddGxb ... re=related
Part 5
http://www.youtube.com/watch?v=4Lqs-2b1 ... re=related
Part 6
http://www.youtube.com/watch?v=eCrlJxR3 ... re=related

Basically, it works like this:

Everybody is born with a set genetic makeup. And every cell in your body has the exact same genetics. But each cell doesnt use all of the genetic information it has. If all our cells were the same, then we wouldnt have distinct organs like skin, bones, brain, etc. Each person's DNA will turn bits of itself on or off depending on genetics, or outside environment. For example, its your genetic instructions that tell your skin cells to turn on the skin cell genes, and turn off your stomach cell genes. Your skin cells dont delete the information about stomach cells, it just turns that information off, and ignores it, while turning on the information about skin cells. That is why, despite having a complete set of all your genetic information, each cell is able to perform a distinct role. This is called epigenetics. It is your epigenetics that determine what parts of your DNA to use, or ignore.

But the outside environment can also influence what genes become active, or inactive. In other words, what happens to you will change your epigenetics. For example, a traumatic event will turn off the genes that regulate your stress response. Its not as though the genes suddenly go away, they are just turned off. This causes you to become more stressed after a traumatic event (more commonly known as PTSD). But, with proper medicine, you can turn those stress reducing genes back on, and feel much calmer. This has been proven in mice at least, but its hopeful to work in humans also. If it proves effective, then it will treat the cause of PTSD, and not the symptoms.

This has also led to a new way to fight cancer. Sometimes, a cell will have its epigenetics changed by either radiation, or replication error, and it will turn off the cancer regulating genes. But with the proper medicine, the cancer regulating genes can be switched back on and the cancer will go into remission.

So, what does this mean for autism?

Consider that identical twins (people who share the same DNA) can have one autistic, and one normal person. So clearly there is more the genetics going on. It is possible that both people have the genes for autism, but those genes are only switched on in one of the twins. In other words, despite having identical DNA, they can use that DNA in different ways, (different epigenetics) resulting in the difference between autism and normality. But what causes this change in epigenetics? It could be an early infection, or perhaps a toxin in the womb, its hard to tell, it could really be anything. It is known that if one identical twin is autistic, then the other twin has a 90% chance of autism. So, whatever triggers the autism in one child, will likely trigger it in the other. This seems to suggest something that happens to both twins, most likely while they were both in the womb.

If you read wikipedia: http://en.wikipedia.org/wiki/Causes_of_ ... Pesticides

It is known that exposure to pesticides during the first 8 weeks of pregnancy will greatly increase the chances of autism. That may suggest that many more people carry the autism gene then 1 in 150, but it isnt used in the majority of people. It is exposure to things like pesticides, or other environmental factors which changes the epigenetics, and triggers the genes to be active.

This also explains why it is difficult to determine the 'autism genes'. The truth is that everybody in your family may carry the autism gene, but you were the only person to have your epigenetics changed in a way which turns on the autism gene. So, looking for a gene that only autistic people have is ineffective, because 10% of the NT population might carry the autism gene without knowing it. It is also possible that if you have the autism gene turned on, then your children will also inherit this gene with the switch already turned on.

This explains why autistic parents are likely to have autistic children. And also autistic children can be born to 'normal' parents who unknowingly passed on the autistic gene in the 'off' mode, but was turned on in their child.

So what does this mean?

Well, so far it isnt known which genes need to be on or off in order for autism to occur. It is possible that switching the gene off will reverse, or lessen the effects of autism. Just like turning on the stress reducing genes can counteract PTSD. However, it is also possible, that the brain is already wired, and changing a gene is like trying to install windows onto a mac computer. Overall, it is at the very least interesting. If you wish to know more information, please watch the full episode on youtube, or check out the wikipedia information on epigenetics:

http://en.wikipedia.org/wiki/Epigenetics

If the epigenetics theory of autism is correct, then it is possible that the condition can be reversed by simply changing the child's diet to something high in epigenetic controllers (it worked in mice). Who knows, those special diets might actually have some basis in reality.

I think science can sometimes make things seem more complicated than they really are. It seems pretty obvious that in some cases with twins, one fetus has been significantly compromised by the other. It isn't rocket-science. It usually never is. If they were to come to any conclusions, or answer questions too quickly, they wouldn't be able to obtain the funds or grants to support their ongoing research. Likewise, it wouldn't be profitable to find any conclusion.

This is probably the best response to the environmental link question, thanks.

There are many, many unforeseen things in the "environment" and so there may not be any "genetic" predisposition at all. They certainly haven't proven any yet and I sort of doubt at this point they ever will. People seem to be attached to a genetic theory but I can't quite imagine why.

Dear aspiartist:
You might want to watch the videos and perhaps read about the evidence before totally ignoring it. The fact you responded in 19 minutes generally tends to indicate you didnt view much of the information.

Yes I am very familiar with the information, thanks though. I've already seen it.

That's very interesting, thanks. I didn't watch the video links, but reading about the study of genetics in general is interesting to me, and especially in autism, even if a tad confusing to my feeble brain. Makes you wonder what it will mean to the field of research in autism in say even another ten years. It's amazing how fast the field of medicine has grown in just a short time. My son with his heart condition wouldn't have even been alive say 20 years ago. Now they're doing open heart surgery on newborns, and even in the womb! It's so amazing.

They throw the "gene" word around a lot in order to maintain the mystique surrounding autism, and likewise continue to line their pockets with research grants and government funds. It's one of the few areas they can actually get away with it because autistic people as a whole have little or no voice with which to really complain. The word "Ghost" gene is most telling and I guess that's as far as they'll go toward admitting there isn't one.

aspiartist:

If it wasn't genetic, then it wouldnt run in families. Since it does run in families, then its not unreasonable to suspect that it is somehow passed from parent to child. Also, the word 'ghost' was just a play on words to describe that something more then genetics is going on. It wasn't an admission that their making things up.

Furthermore, what part of their evidence do you disagree with? Do you think the rats were switched out when nobody was looking? To just bluntly say that the well documented evidence is a hoax without any contrary evidence of your own is paranoia.

Autism has become a very broad category of illnesses, unfortunately, and is likely where all the confusion rests. Not much will ever be defined within that framework.

However that may be, it's not a sufficient explanation for the actual findings of research.

Concordance studies have consistently demonstrated that identical twins have a high but not 100% rate of concordance for autism, and that there is a lower yet statistically significant rate of concordance between non-twin siblings. Clearly non-twin siblings are not significantly compromising the fetus of their sibling/s, especially where the sibling happens to be older.


The person or group who provide a definitive answer and demonstrate that it is correct, will benefit from doing so far beyond any benefit to be derived from not finding the definitive answer and demonstrating its correctness. Significant discoveries such as that would be, tend to have significant rewards, including fame, fortune, the respect of one's peers etc.

The study explains how genes operate and then goes on to say that environment changes the actual genes themselves and not the other way around. This I know is true, as in the case of trauma. They've explained that very well.

In other words the deviations are environmentally caused.

it really seems like there's a genetic predisposition to certain things that can be further influenced by environmental factors, but neither on it's own 100% explains everything


Jeff

The environment is complex and has a profound effect on genes and DNA. Ultimately, "environmental" factors are powerful in how much it can change and affect us.

Environmental factors, yes.. I believe environmental factors play a huge part as well as genetics. Interesting info and definitely so much to take in. I haven't watched the videos yet and I will have to set aside time to do so. I believe autism is definitely genetic. My uncle has it, I wouldn't be surprised if my father has AS, my mother is not under the spectrum and neither is my brother.. I am obviously under the spectrum, so is my son but my daughter is not (but she has ADHD, which I also have). So I guess in her case the genes were turned off.