Autism's Tangled Genetics Full of Rare and Varied Mutations

Several new studies highlight the complexity of autism's genetic roots, revealing why it strikes boys more than girls and offering clues for possible new treatments















Share on Tumblr


Screening and treatment
By better understanding the numerous routes autism can take to perturbing common pathways, new avenues of treatment might open up sooner. Currently, treatment is based on behavior or serendipity, State says, adding, "we're very far behind other areas of medicine in that respect." But, he says, if a genetic screen can find even a rare mutation in a child before symptoms appear—or even in utero—behavioral therapy could start earlier, improving that child's level of functioning.

And for pharmaceutical development, if treatments can be pinpointed to improving a common pathway, rather than fixing a particular genetic error, they might be able to treat a wider range of ASD patients instead of each individual type of mutation. But interventions like these are "easier said than done," Zoghbi notes. "There are lots of proteins involved and lots of genes involved."

Genetics are, of course, just part of the increasingly complex autism puzzle. "Two people can have exactly the same mutation" and not have the same degree of developmental disorder, State says. "The question of why is the multimillion-dollar question."

To help sort out this increasingly urgent answer, Gregory advocates for a broad-spectrum approach. "It's not going to be one thing, it's going to be a collection," he says. "Between genetic, genomic and epigenetic, we'll identify what causes the spectrum." (Epigenetics refers to the environmental modification of genetic activity; such changes can be heritable.) And within these, the environment is often another complicating factor, as a person's genetic makeup can render them more or less sensitive to environmental influences—whether that is from social bonding or purported chemical influences.

But one thing is well established in autism research: as scientists look deeper into the disease the complexities multiply almost exponentially. Gregory suggests that one of the next steps will be to assess the mechanisms behind epigenetic influences in autism. But "that becomes a harder thing to answer," he says, speaking from experience in that field. DNA methylation and its effect on genes varies in different types of tissue, adding another layer of challenge to parsing the interdependent effects.

The other research teams are also hard at work on the next batch of studies. State's group is expanding their study to include some 1,600 more families as well as homing in on gene regions that they have already found.

The rush of studies in the past couple years has been thanks in large part to technological advances as well as a push to study the disease more closely. "The down payment in the early part of this century is really paying off," State says. But Gregory is eagerly anticipating "the next big leap forward" in higher-resolution sequencing, which will allow is group and others to "identify these very small changes" that researchers are now only just getting a taste of.



36 Comments

Add Comment
View
  1. 1. GeorgieWood6 07:48 PM 6/8/11

    When do you give up on genetics and say that something else is causing Autism? Isn't there enough evidence already suggesting that in most children something in the environment is causing Autism?

    Reply | Report Abuse | Link to this
  2. 2. Bops in reply to GeorgieWood6 08:48 PM 6/8/11

    No, There is no question that it's genetic. The denial some parents have stands in the way of the reality.

    There was a good article about "Why Smart People Believe Weird Things".
    It maybe a book too. I'm sure you can find it in the search here.

    Denial is the real problem. Years of environmental proof is just not there. I'm sorry, it's the truth.

    Reply | Report Abuse | Link to this
  3. 3. conn0r 10:10 PM 6/8/11

    Bops, I agree its largely genetic. However, nothing in the world is absolute (except the US's poor soccer), but I wonder to what degree epigenetics play a part in autism.
    Ever since studying epigenetics in college, I've found myself frustrated by its lack of mention. With all genetic issues, epigenetics is something worthy of consideration, and it never seems mentioned in these type of articles.

    Reply | Report Abuse | Link to this
  4. 4. coolynn 11:07 PM 6/8/11

    Could this be the first sign of human beings mutating right before our eyes?

    Reply | Report Abuse | Link to this
  5. 5. Unksoldr 11:31 PM 6/8/11

    You got that right Cool! My Asperger's has made life for me challenging but very rewarding. It's evolution at work, sometimes you get the Rainman and sometimes you get a Green Beret with an IQ of 138.

    Reply | Report Abuse | Link to this
  6. 6. sjn 11:58 PM 6/8/11

    Why do we continue to think of environment and genetics as two discrete, non-interacting either/or spheres? Why for example, does this very article basically throw away without further comment the most concrete observation- that girls are 1/4th as likely to manifest autistic characteristics - because they are more "socially inclined" therefore more "resistant" to genetic variations? This "social inclination" is basically a learned phenomena based on how we treat and raise boys vs. girls and it gets no further discussion at all. Instead we go back to looking for genes we can manipulate by pharmacology. That may or may not have any future value, but the very article implies we need more more integrated focus on how/what learned behaviors give this increased "resistance" to the genetic variations we attempt to link to ASD.

    Reply | Report Abuse | Link to this
  7. 7. jtdwyer in reply to Unksoldr 12:34 AM 6/9/11

    I also suspect that I 'suffer' from Asperger's (my life has been an 'interesting' experience), but there was certainly no testing when I was a child in the 1050s. I do have a gifted grandson that has been diagnosed and two very interesting granddaughters.

    Also interesting is that the population of the world will soon have tripled in my lifetime while the rural populace has increasingly migrated to cities. While I think this is an extremely high risk strategy for humanity, it most certainly changes the demands for individual survival strategies in ways that are not completely understood. Everyone now seems to communicate most intimately with personal electronics devices and social networks... Perhaps 'normal' has already changed, leaving pseudo-psycho-science behind.

    This article states:
    "...To help sort out this increasingly urgent answer, Gregory advocates for a broad-spectrum approach. "It's not going to be one thing, it's going to be a collection," he says. "Between genetic, genomic and epigenetic, we'll identify what causes the spectrum.""

    How could it be otherwise when such a broad spectrum of symptoms and varying degrees of disability have already been thrown together a single condition? There is almost no hope of finding a single solution for such a 'broad spectrum' of disorders. In fact, some of these symptoms could be beneficial adaptations to broadly changing conditions.

    Not to say that many if not most of those affected with classical Autism symptoms are not profoundly disabled. But to make such generalizations as:
    "Although autism has been established as a genetically based disease, it does not seem to be passed along in families in the same way that Huntington's disease is. Because those with ASD rarely end up having children of their own, mutations are unlikely to become widespread in populations."

    is ludicrous. If you surveyed those with Asperger's I suspect you'd find that they are outliers in your sample population. My biggest fear for my grandson is that his diagnosis will lead to social and/or medical bureaucratic ostracization - or worse.

    Who knows - perhaps it is those who can see the world differently that will be necessary to save it.

    Reply | Report Abuse | Link to this
  8. 8. phalaris 09:03 AM 6/9/11

    I've seen it argued that the apparent increasing incidence of ASD's could be due to more assortative mating taking place. In modern society, it could be that like is meeting like more often, and drawing consequences. If both sides have a disposition to ASD, the chances that offspring will have the overt syndrome are perhaps higher.
    There have been suggestions that ASD style traits are more common in sciency types. With access to college being easier nowadays, couples with that disposition are finding each other and producing kids with stronger versions of the trait.

    Reply | Report Abuse | Link to this
  9. 9. fgomez in reply to phalaris 09:33 AM 6/9/11

    Although you may be partially correct, it would be close to impossible to test for any kind of assortative mating with such a large populous. It may be more beneficial if we first isolated some epigenetic influences because it seems that is where most problems are occurring. By studying families and how they interact with their children who have autism may be a better start for the future of understanding this disease better. Then, maybe, if it becomes more possible you can then start testing for some kind of assortative mating influences. The current progress of understanding for this disease is in a very good spot. Rome wasn't built in one day.

    Reply | Report Abuse | Link to this
  10. 10. SteveinOG 11:42 AM 6/9/11

    Has anyone studied relation of sonograms performed during fetal development and later emergence of autism?

    Reply | Report Abuse | Link to this
  11. 11. HowardB 02:15 PM 6/9/11

    A really excellent article and some great comments. As I read it I could not help wondering about the one topic not mentioned. The categorisation of sufferers of ASD. I see no mention of how sophisticated they are categorised or if it done at all. It would seem to me that starting with well categorised sufferers DNA is critical to drawing conclusions from the DNA analysis.

    Reply | Report Abuse | Link to this
  12. 12. jbrever in reply to coolynn 07:22 PM 6/9/11

    Hi! Yah i'd say you are correct Coolynn, a mutation. Would you like an explanation based on genetics, among other things? - visit www.jovianarchive.com.

    Reply | Report Abuse | Link to this
  13. 13. Planet4321 02:30 AM 6/10/11

    A lot of "hunches" and contrived reasons here. Humans are generally not too intelligent or creative and it takes decades for a society to resolve anything, only to create another problem because of that lack of intelligence. It seems all advancements are cancelled by humans themselves. How long ago was it that humans knew blood circulated through the body? Not too long ago. Genetics,etc? What is not a part of genetics? Humans have not figured out what is "normal" genetics and yet they venture to define. The silly idea that autism can be cured through social intervention is incredibly primitive and just a sad act of desperation...otherwise autism would have been " cured" already. Behavioral,etc. intervention does have a degree of success, because it effects the symptom. Humans don't know much about how the brain operates, and until they do....autism and many other "defects" will not be treatable.

    Reply | Report Abuse | Link to this
  14. 14. Planet4321 02:35 AM 6/10/11

    Assortative mating is true for many issues, and thinking of it as the cause is ridiculous. It's virtually not worth mentioning. It certainly offers no cure. Thinking is certainly not taught enough in US schools.

    Reply | Report Abuse | Link to this
  15. 15. zstansfi in reply to sjn 04:12 AM 6/10/11

    Well, we don't continue to think about environment and genetics as separate spheres. That time has long since passed. I think the key issue is that it is still difficult to integrate genetic and environmental data on the broad scale seen in these kinds of studies. This isn't all that surprising, I mean GWAS didn't even exist >10 years ago. It will be interesting to see what happens when we start throwing in more environmental variables as well as gene expression data.

    Reply | Report Abuse | Link to this
  16. 16. Wizardwayne 10:59 AM 6/10/11

    If there is such a broad range of genetic mutations than can account for ASD, then why is it that 1 in 150 kids have it? That's just way too widespread for so may mutations to be necessary. I believe that it HAS to be something that virtually all kids are exposed to and means environmental, diet-related or common medical-related practices. May genetic mutations in so many people would be quite rare.

    Reply | Report Abuse | Link to this
  17. 17. Wizardwayne 10:59 AM 6/10/11

    If there is such a broad range of genetic mutations than can account for ASD, then why is it that 1 in 150 kids have it? That's just way too widespread for so may mutations to be necessary. I believe that it HAS to be something that virtually all kids are exposed to and means environmental, diet-related or common medical-related practices. May genetic mutations in so many people would be quite rare.

    Reply | Report Abuse | Link to this
  18. 18. jbrever 11:30 AM 6/10/11

    What if the, "many genetic mutations (occurring) in so many people" is actually an evolutionary change that as, a system change, in us started hundreds of years ago and is only now making it's way to the surface? A lot of the time Science is like trying to find a needle in a haystack. But i do enjoy the search.

    Reply | Report Abuse | Link to this
  19. 19. zstansfi in reply to Wizardwayne 03:32 AM 6/11/11

    "If there is such a broad range of genetic mutations than can account for ASD, then why is it that 1 in 150 kids have it?"

    Well, that's the whole point--ASD is not a "single" disease. It's a spectrum of behaviour which is thought to be produced by a wide variety of genetic mutations. Nobody with an ASD diagnosis has all of the possible mutations that are associated with ASD. Rather, each person just has a few specific mutations which may make them susceptible to developing this disorder. This probably isn't the whole story as it's likely that many factors interact with these mutations to produce ASD. However, there's no reason to believe that there is some sort of environmental toxin or dietary deficiency which is causing people to develop this disease.

    Reply | Report Abuse | Link to this
  20. 20. phalaris in reply to Planet4321 09:09 AM 6/11/11

    I didn't go to a US school, and if I just went by your response I'd have to conclude that reading and manners aren't taught in the US either. Where did I say that assortative mating was the cause of ASD? I posited a possible partial explanation for the alleged increase in this condition. It wasn't my idea: it came from someone who has high post-grad qualifications in biology.

    Reply | Report Abuse | Link to this
  21. 21. lirael 02:03 AM 6/14/11

    One of the problems with girls/women and ASD is that many end up diagnosed wrongly, for example as borderline. How can you make decisions on genetics when the diagnoses is still in its infancy? Another question: might ASD be in fact a collection of different disorders?

    Reply | Report Abuse | Link to this
  22. 22. sunnystrobe 05:55 AM 6/14/11

    The world would be much poorer without the odd (!) Asperger gene combinations, which, by way of this marvelous Mendelian gene shuffling game, have led, and are leading, to the odd genius - think: Mozart & Beethoven and such ilk....
    One could possibly classify the majority of creative artists , if not as 'Aspi's' (on the widest possible spectrum) , then plain & simply as extreme introverts; and Comparative behaviorology gives us an evolutionary insight into this phenomenon, too: Every dog breeder knows full well that in each litter there are wide variations possible amongst its puppies regarding their aptitude towards sociability training;
    cf. a wild wolf's behavior with a guide dog's 'empathy' into a blind person's needs...
    Domestication-cum- civilization must have worked mighty changes in our H. S.S. prefrontal department, too!
    The fact that autism has grown tenfold or more in the past three or four decades, however,clearly points to some environmental changes influencing babies' brain developments, apart from their 'given' genes cocktail.
    Dietary influences are the most likely culprits.
    I am constantly astounded that the role of dietary deficiencies is being almost always totally ignored or negated ( see under 19).
    The role of essential fatty acids such as the omega3/omega6 ratio in brain health ( both in fetal neuronal development and, later, in Alzheimer's disease) is now clearly coming to the fore.
    'Frankenstein' fats such as transfatty acids might have a lot to answer for, amongst many other dumb diet changes from natural to denatured. (youthevity.com)


    Reply | Report Abuse | Link to this
  23. 23. Max Redalia 08:46 PM 6/15/11

    If autism is genetic, where are all the 80-year old autism cases?

    Vaccines exist for a reason.

    They make drug companies rich, selling drugs to treat autoimmune diseases caused by vaccination.

    The drug makers main source for info on the safety of thimerosal, Poul Thorsen, was recently indicted for fraud and grand larceny in connection with his thimerosal research. He was hired by drug companies to commit fraud so they could keep poisoning children. Eli Lilly Co. owns the patent on thimerosal. Who was head of Lilly after he left the CIA? George Herbert Walker Bush.

    This vaccine/autoimmune illness link has been common knowledge in the medical research field since June, 2000, when the first Vaccine Safety Datalink Study results read at Simpsonwood, Ga. showed a tenfold increase in a wide array of neurological problems associated with infant vaccines. They saw increased reading delays, speech delays, autism, tics and mood disorders, which scared them so badly they immediately began discussing ways to bury the data and commit fraud.

    What was the most common diagnosis? "Misery and Unhappiness Disorder." What is one the most common symptoms of mercury poisoning? Depression.

    The mechanism is called a "Type IV Delayed Immune Hypersensitivity," and it can trigger immune attacks against healthy tissue, days or years after vaccination. The other adjuvants and preservatives in vaccines (aluminum, antibiotics, etc.) interact with lead and testosterone to cause even higher rates of damage to males, resulting in the 4-to-1 sex disparity in autism. But please, go on poisoning your children. Kids are FAR less important than drug company profits from causing childhood diabetes, autism, ADD, ADHD, depression, asthma and Guillain-Barre Syndrome, among others.

    All of which increased among children after additions to the children's vaccine schedule, and skyrocketed since George H.W. Bush mandated the day of birth HepB shot in 1989.

    Reply | Report Abuse | Link to this
  24. 24. Max Redalia 08:46 PM 6/15/11

    One hilarious aspect of this public health disaster is the rate of autism in Atlanta, Ga. was discovered in 1996 to be far higher than the rest of the nation.

    http://www.medscape.com/viewarticle/447240

    This is most likely the result of parents playing the role of good little cattle, herding their calves in to be vaccinated under the watchful eye of Atlanta's "Centers for Disease Control." Interesting name, that.

    It's not the Centers for Disease PREVENTION, or the Centers for Disease ERADICATION. No, it's all about CONTROL. They want to control who gets sick. Judging from the one-in-six rate for neurological trouble in American kids, they're doin' a bang-up job.

    Reply | Report Abuse | Link to this
  25. 25. skybluskyblue 03:27 PM 6/16/11

    "This "social inclination" is basically a learned phenomena based on how we treat and raise boys vs. girls and it gets no further discussion at all. Instead we go back to looking for genes we can manipulate by pharmacology."
    I think a large part of the difference is the different sex hormone ratios in girls vs boys not purely environment.

    Reply | Report Abuse | Link to this
  26. 26. skybluskyblue in reply to Max Redalia 03:37 PM 6/16/11

    Unusual conclusions require unusually strong proof. So, put up or shut up. How is anyone to know if your assertions are not just ravings of a paranoid personality?

    Reply | Report Abuse | Link to this
  27. 27. wonadewona 02:43 PM 6/17/11

    If people are still blind enough to think this epidemic is in the genes then i despair..wake up..its ALL vaccine damage/enviromental... playing on certain people with certain genes/predispositions ..god ..a monkey could work it out ..big pharma does not want anyone to catch onto this,and that is the truth..there is a rise in asd disorders that directly correlates to the rise in vaccine scedule...when will the general public wake up from the damn slumber and listen to the parents ,who have seen it all with their own eyes.!!!!

    Reply | Report Abuse | Link to this
  28. 28. wonadewona in reply to GeorgieWood6 02:44 PM 6/17/11

    exactly...at least someone is awake here.

    Reply | Report Abuse | Link to this
  29. 29. wonadewona in reply to Bops 02:47 PM 6/17/11

    try talking to the thousands of parents that you just swept aside with those uneducated statements... ask them whether they saw their child disapear after vaccinations or not..ask them if their child has biological problems like gut issues,and then ask if they have solved them with certain interventions,,proving this is biological... try asking the parents for the truth smart arse.

    Reply | Report Abuse | Link to this
  30. 30. wonadewona in reply to phalaris 02:53 PM 6/17/11

    for goodness sake.!!! its an epidemic...there is no such thing as an genectic epidemic...im surrounded by fools..no wonder the poor parents of all these children are tearing their hair out...why wont anyone listen to them??? the vaccines are the most likely cause in this,,it is those which have gone up in number along with the rise in asd ,and it is those that give children the bodies full of toxic crap..the metals in the vaccines compromise the immune system ,and also they are causing encephalitis ... if you do not all listen to the parents soon,you will be listening to the crap science forever and in the meantime your children and grand children too will be injured..its only a matter of time

    Reply | Report Abuse | Link to this
  31. 31. wonadewona in reply to SteveinOG 02:55 PM 6/17/11

    no,,because the children in poor countries do not get that,,but what they are now getting is more vaccines instead of help with better sanitation and clean water..and now watch, the asd rates climb.

    Reply | Report Abuse | Link to this
  32. 32. Max Redalia in reply to skybluskyblue 04:51 PM 6/17/11

    Well, you could try doing some research, the transcript of the Simpsonwood meeting where doctors and industry reps conspired to commit fraud is available online.

    http://www.autismhelpforyou.com/HG%20IN%20VACCINES%20-%20Simpsonwood%20-%20Internet%20File.pdf

    How is anyone to know if your complacent platitudes are not the product of an industry hatchet man? The drug companies opinion that injecting aluminum, mercury and other toxins into babies is harmless is the unusual conclusion. Where's your proof it's safe? You have none.

    Reply | Report Abuse | Link to this
  33. 33. skybluskyblue 05:16 AM 6/30/11

    "If autism is genetic, where are all the 80-year old autism cases?" My father an engineer [typical profession for one end of the spectrum] is in his 70s. I am officially diagnosed and I am 45. Then realize that many people diagnosed with "mental retardation" in the past are now more correctly diagnosed with an ASD.

    If vaccines are to make $$ then why do poor and developing countries do their best to manufacture their own vaccines? This includes communist and socialist countries who give them to their citizens for free. As a person who bought vaccines for an animal hospital I can tell you that they were no money maker for us or the manufacturer. The only expensive vaccines were the newer less used vaccines, for example the Lyme disease vaccines. The vaccine that was required by law, Rabies, was the least expensive and we did not overcharge for it.
    Pediatricians will tell you the same sort of story, so unless they all lie, like the exciting plot of an X-files episode [this why you guys all believe this stuff, it is SO exciting, huh?], your idea is just plain incorrect.

    Reply | Report Abuse | Link to this
  34. 34. skybluskyblue in reply to Max Redalia 07:53 AM 6/30/11

    If you are going to do proper research you need to cite original documents not an "autism for you" site, or at least from a neutral source. As far as this old canard about Simpsonwood, its supposed nefarious content has been debunked. See Wikipedia: "Salon magazine later corrected the article multiple times for factual errors and ultimately retracted the article." 2000 Simpsonwood CDC conference: Wikipedia. This mercury theory also has been debunked many times over. Now the latest X-files "episode" is about "Too many, Too soon". But watch out, "trust no one!"

    BTW, Aluminum combines with mercury only if aluminum is in its "elemental" form, not when aluminum is in a salt form as it is in microgram amounts in some vaccine adjuvants.


    Reply | Report Abuse | Link to this
  35. 35. skybluskyblue 08:59 AM 6/30/11

    Again, mercury poisoning is nothing like autism. I do not know any autistic person whose skin is pealing off whose skin is pink, who sweats profusely, who has high blood pressure from no other cause, who is losing teeth, hair and nails, who has kidney dz from no other cause etc. These ideas are fabrications grabbed desperately for those looking for a scapegoat. Just read up on mercury poisoning yourself, not from some one who has an axe to grind or money to make (like product liability lawyers).

    Reply | Report Abuse | Link to this
  36. 36. skybluskyblue in reply to sjn 10:04 AM 6/30/11

    "This "social inclination" is basically a learned phenomena based on how we treat and raise boys vs. girls and it gets no further discussion at all."

    Have you never thought of hormone differences? The idea that social inclination is mostly a "learned phenomena" has been proven false. Sure, our culture has stereotypes for men and women, but such powerful things like our hormones [ever feel the strong desire to get romantic when you were a teenager?] influence many systems in our bodies, thus at least one of these systems "gets though" to our social behavior.

    As a female with an ASD I am a little different from my nephew with the same syndrome. He is quite a bit more interested in collecting things from vacuumes to records [without caring about the music on them] to crystals and many more objects. I was more interested in very few subjects in intense ways. Socially, I am different from my nephew, but we both have difficulties keeping friendships going if the other person is a person focusing on conformity to the majority society.

    Just like many genetic traits the variation to extremes, like a very tall kid, can have advantages and sometimes disadvantages. If those around the person with one type of extreme act helpful and try to accommodate and help them learn to adapt, life can turn out better; but if the person is shunned or singled out and treated negatively the consequences can be difficulty for everyone.

    Just because someones dose not speak does not mean they cannot hear; just because someone does not look at you does not mean they do not know that you are talking about them or reacting to them. The autistic child is NOT "gone"; they are merely thinking and behaving differently than you. Don't panic.

    You need "The Hitchhiker's Guide to the Autistic Galaxy" and you may need a "Babel fish" [ See the book: The Hitchhiker's Guide to the Galaxy] to translate; but you are not in a situation where suicide or despair is the best course of action. In this book the protagonist is taken up away from earth and he relies on his host to help him out, thus similarly, you let them guide you as to how to act in this new world. Sure, you can help out your host and you may use aides to help conduct yourself here, but changing your host or your new world is not your primary job. Be gracious and DON'T PANIC.

    Reply | Report Abuse | Link to this
Leave this field empty

Add a Comment

You must sign in or register as a ScientificAmerican.com member to submit a comment.
Click one of the buttons below to register using an existing Social Account.

More from Scientific American

Follow Us:

See what we're tweeting about

Scientific American MIND

More »

Free Newsletters


Get the best from Scientific American in your inbox

Solve Innovation Challenges

Powered By: Innocentive

  SA Digital
  SA Digital

Science Jobs of the Week

Email this Article

Autism's Tangled Genetics Full of Rare and Varied Mutations

X
Scientific American Mind

Subscribe Today

Save 66% off the cover price and get a free gift!

Learn More >>

X

Please Log In

Forgot: Password

X

Account Linking

Welcome, . Do you have an existing ScientificAmerican.com account?

Yes, please link my existing account with for quick, secure access.



Forgot Password?

No, I would like to create a new account with my profile information.

Create Account
X

Report Abuse

Are you sure?

X

Institutional Access

It has been identified that the institution you are trying to access this article from has institutional site license access to Scientific American on nature.com. To access this article in its entirety through site license access, click below.

Site license access
X

Error

X

Share this Article

X