Study shows California's autism increase not due to better counting, diagnosis

Jan 08, 2009

A study by researchers at the UC Davis M.I.N.D. Institute has found that the seven- to eight-fold increase in the number children born in California with autism since 1990 cannot be explained by either changes in how the condition is diagnosed or counted — and the trend shows no sign of abating.

Published in the January 2009 issue of the journal Epidemiology, results from the study also suggest that research should shift from genetics to the host of chemicals and infectious microbes in the environment that are likely at the root of changes in the neurodevelopment of California's children.

"It's time to start looking for the environmental culprits responsible for the remarkable increase in the rate of autism in California," said UC Davis M.I.N.D. Institute researcher Irva Hertz-Picciotto, a professor of environmental and occupational health and epidemiology and an internationally respected autism researcher.

Hertz-Picciotto said that many researchers, state officials and advocacy organizations have viewed the rise in autism's incidence in California with skepticism.

The incidence of autism by age six in California has increased from fewer than nine in 10,000 for children born in 1990 to more than 44 in 10,000 for children born in 2000. Some have argued that this change could have been due to migration into California of families with autistic children, inclusion of children with milder forms of autism in the counting and earlier ages of diagnosis as consequences of improved surveillance or greater awareness.

Hertz-Picciotto and her co-author, Lora Delwiche of the UC Davis Department of Public Health Sciences, initiated the study to address these beliefs, analyzing data collected by the state of California Department of Developmental Services (DDS) from 1990 to 2006, as well as the United States Census Bureau and state of California Department of Public Health Office of Vital Records, which compiles and maintains birth statistics.

Hertz-Picciotto and Delwiche correlated the number of cases of autism reported between 1990 and 2006 with birth records and excluded children not born in California. They used Census Bureau data to calculate the rate of incidence in the population over time and examined the age at diagnosis of all children ages two to 10 years old.

The methodology eliminated migration as a potential cause of the increase in the number of autism cases. It also revealed that no more than 56 percent of the estimated 600-to-700 percent increase, that is, less than one-tenth of the increased number of reported autism cases, could be attributed to the inclusion of milder cases of autism. Only 24 percent of the increase could be attributed to earlier age at diagnosis.

"These are fairly small percentages compared to the size of the increase that we've seen in the state," Hertz-Picciotto said.

Hertz-Picciotto said that the study is a clarion call to researchers and policy makers who have focused attention and money on understanding the genetic components of autism. She said that the rise in cases of autism in California cannot be attributed to the state's increasingly diverse population because the disorder affects ethnic groups at fairly similar rates.

"Right now, about 10 to 20 times more research dollars are spent on studies of the genetic causes of autism than on environmental ones. We need to even out the funding," Hertz-Picciotto said.

The study results are also a harbinger of things to come for public-health officials, who should prepare to offer services to the increasing number of children diagnosed with autism in the last decade who are now entering their late teen years, Hertz-Picciotto said.

"These children are now moving toward adulthood, and a sizeable percentage of them have not developed the life skills that would allow them to live independently," she said.

The question for the state of California, Hertz-Picciotto said, will become: 'What happens to them when their parents cannot take care of them?'

"These questions are not going to go away and they are only going to loom larger in the future. Until we know the causes and can eliminate them, we as a society need to provide those treatments and interventions that do seem to help these children adapt. We as scientists need to improve available therapies and create new ones," Hertz-Picciotto said.

Hertz-Picciotto and her colleagues at the M.I.N.D Institute are currently conducting two large studies aimed at discovering the causes of autism. Hertz-Picciotto is the principal investigator on the CHARGE (Childhood Autism Risk from Genetics and the Environment) and MARBLES (Markers of Autism Risk in Babies-Learning Early Signs) studies.

CHARGE is the largest epidemiologic study of reliably confirmed cases of autism to date, and the first major investigation of environmental factors and gene-environment interactions in the disorder. MARBLES is a prospective investigation that follows women who already have had one child with autism, beginning early in or even before a subsequent pregnancy, to search for early markers that predict autism in the younger sibling.

"We're looking at the possible effects of metals, pesticides and infectious agents on neurodevelopment," Hertz-Picciotto said. "If we're going to stop the rise in autism in California, we need to keep these studies going and expand them to the extent possible."

Source: University of California - Davis

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deatopmg
1 / 5 (1) Jan 08, 2009
"We're looking at the possible effects of metals, pesticides and infectious agents on neurodevelopment," Hertz-Picciotto said. "If we're going to stop the rise in autism in California, we need to keep these studies going and expand them to the extent possible." - translated, that means keep paying our salaries.

If they REALLY want to minimize Autism they'd better include studies of the blood level of vitamin D in the mothers and in the austisic children.

The intense fear of sun exposure (which makes vitamin D in the skin) that has been instilled in us by the industrial cosmetic and medical industries has resulted in an epidemic of illnesses (cancers, heart related diseases, autism, to name a few) related to vitamin D deficiencies. And who reaps the benefits of that induced fear??
Arkaleus
1 / 5 (2) Jan 08, 2009
It worries me that the increase in Autism could be a genetic trend. Has our culture bred disease into itself because of how we couple and reproduce? Are good genes dying out because intelligent individuals are unwilling to marry and live in a diseased and destructive cultural illusion?

Maybe it's time to finally admit our system of marriage needs to be less about wealth and social status and more about producing excellent children.
superhuman
not rated yet Jan 09, 2009
This is a extremely important study! It proves beyond any doubt that there is an environmental factor!

In all probability there is a genetic factor which predisposes certain families to autism and there is the real cause which is some unknown chemical agent, which induces the disease in those who are genetically susceptible.

It also can't be ruled out that in some rare cases genetics alone is enough to induce the disease, but the 700-800% increase means that environmental factors play a huge role (genetic factors can't change significantly during such a short time).

It has to be some sort of chemical most likely added to some product. It could be anything a pesticide, a food preservative or supplement, a cosmetic, a medicine, a cleaning agent, a paint, a heavy metal or other environmental pollution, a natural substance present in water or food supplies, the list goes on.

It would be great if families with autistic children could compile (perhaps online) the list of all the products that they were using before and during the pregnancy and before the disease was diagnosed. It would certainly help investigators pinpoint the fatal agent.

Another complementary approach is to compare all the products sold in California during the last 15 years and find those which are consumed in greater number in California then in the rest of the country. The increase in consumption should follow the trend in disease increase (with correction for time from onset to diagnosis).

By comparing the lists of products used by families with list of products which are sold in greater numbers in California then in the rest of the country it should be possible to find the cause or at least narrow the search considerably.

There is also one other piece of advice stemming from this study. Families who have one autistic child and consider having another child should:
1. Emigrate (at least temporarily) to a country and region which have the lowest worldwide incidence of autism (but good diagnosing)
2. Stop using all and I mean all products they have been using before and after the pregnancy which resulted in the first autistic child.

This doesn't of course guarantee anything but it at least significantly lowers the chances of having a second autistic baby.

The 600% increase reported in California means the substance responsible plays a significant role in the onset and therefore families with one autistic child can minimize the chances of having another by changing their environment to one which has the least chances of having this substance, they should also eliminate the chances of taking the substance with them (for example by having their favorite products shipped to them from their country of origin).

As I said this is a very important study, it might be a breakthrough needed to finally solve the puzzle of this enigmatic disease.
Velanarris
1 / 5 (1) Jan 09, 2009
This is a extremely important study! It proves beyond any doubt that there is an environmental factor!

In all probability there is a genetic factor which predisposes certain families to autism and there is the real cause which is some unknown chemical agent, which induces the disease in those who are genetically susceptible.

It also can't be ruled out that in some rare cases genetics alone is enough to induce the disease, but the 700-800% increase means that environmental factors play a huge role (genetic factors can't change significantly during such a short time).


Not so fast, there are multiple other factors at play, such as the average age of motherhood, which has been shown to increase the chances of birth defects and other maladies, that are missing from this study. The increase in autism could be wholly linked to the social behavior of the mothers. The social climate in regards to planned parenting have changed where the average age of mothers has risen from 21 to 25 in the US. Although this increase appears small, when you realize there are over 4 million new mothers since the last federal census, 15% of which were over 40 when they had their first child, it shows there is a lot more research to be done.

I don't discount the environmental link but you can't state that it's an absolute truth when there are other factors potentially at play. Especially in a state where the majority of mothers are working mothers who may have focused on a career first and put off parenting until their 30's and 40's.
superhuman
not rated yet Jan 09, 2009
I think you don't understand, the risk rose 700 percent(!) during less then 20 years and only in California!

If it were due to mothers age a similar rise would have to be recorded in all diseases related to mother's age, like down syndrome for example.

No mysterious 'social behavior of mothers' can explain such results either, social behavior is never so well delimited by state borders and it doesn't change that rapidly on the scale of whole populations.
Velanarris
1 / 5 (1) Jan 09, 2009
I think you don't understand, the risk rose 700 percent(!) during less then 20 years and only in California!

If it were due to mothers age a similar rise would have to be recorded in all diseases related to mother's age, like down syndrome for example.

No mysterious 'social behavior of mothers' can explain such results either, social behavior is never so well delimited by state borders and it doesn't change that rapidly on the scale of whole populations.

But there is no included data for other states or regions in this research. The question of environment vs genetic causation isn't being answered in a report with such limited scope. The CDC statistics show a marked rise in the reported cases of down sydrome in California as well as over the entirety of the US.

The problem with trying to correlate DS and ADS is that DS is known to have a higher occurance in the children of women over age 35 but Autism and other ADS do not have a proven meiotic/genetic link. There are strong indicators for sure, but with ADS patients showing such a large amount of altered genes and a detriment to so many brain interactions and areas, such a link is an example of correlation rather than causation.

The basis could be environmental, but more research is needed to establish that as fact.
Velanarris
1 / 5 (1) Jan 09, 2009
Forgot the link.

Statement on CDC statistics for down syndrome.

http://www.cbsnew...61.shtml
Velanarris
1 / 5 (1) Jan 09, 2009
In line with this is the fact that DS itself has a 2000% probability increase in women over age 35, from 1 in 100 to 1 in 2000. That is even greater than the 700% increase in ADS noted in California over 20 years.

If the attitude change from stay at home young mother to career first took place in a generation, then the 700% increase is well in line with a social cause rather than an environmental cause.
BenD
not rated yet Jan 09, 2009
I would agree with several commenters than average maternal age seems to be a large possibility. Larger maternal stress loads might also play a part. However, I think that environmental causes play a minor role, if any, in this increase.

Reasoning: Environmental causes would actually have been higher in the 80's than now due to the massively reduced pollution levels. The rise of organic produce may have increased heavy-metal consumption, but the effects of that would be minor in comparison. Indoor pollutants may build up more due to better energy efficiency, but those are mostly allergenic items. Polystyrene and other plastics have greatly reduced their offgassing due to increased industrial recovery efficiency, so that wouldn't be a problem.

As mercury was removed from vaccines with no change in autism trends, thymerosal cannot have had a significant effect.

Indeed, I cannot see any environmental cause that would have increased since the 80s with the sole exceptions of increased medication, organic produce, and indoor air pollutants such as radon. The toxicity of practically everything else has decreased in the intervening two decades.
x646d63
not rated yet Jan 09, 2009
Indeed, I cannot see any environmental cause that would have increased since the 80s with the sole exceptions of increased medication, organic produce, and indoor air pollutants such as radon. The toxicity of practically everything else has decreased in the intervening two decades.


How about food additives? Aspartame, MSG, nitrates/nitrites, phosphates?

How about food derivatives? HFCS, Soy?

I blame highly processed foods and food additives. And I make that claim citing no evidence to support it.
Velanarris
1 / 5 (1) Jan 09, 2009
Indeed, I cannot see any environmental cause that would have increased since the 80s with the sole exceptions of increased medication, organic produce, and indoor air pollutants such as radon. The toxicity of practically everything else has decreased in the intervening two decades.


How about food additives? Aspartame, MSG, nitrates/nitrites, phosphates?

How about food derivatives? HFCS, Soy?

I blame highly processed foods and food additives. And I make that claim citing no evidence to support it.

Processed food is absolutely horrid for your system, I'm sure it's also horrid for developing fetuses as well, but does it cause autism? Answer is, "I have no idea."
superhuman
not rated yet Jan 09, 2009
But there is no included data for other states or regions in this research.

Since the authors don't mention the rest of US it implies such a pronounced raise is not present in the other states, or maybe it is just omitted from physorg piece. But even if it were more widespread in it doesn't change much, only the search for the cause should be adapted accordingly.

The question of environment vs genetic causation isn't being answered in a report with such limited scope. The CDC statistics show a marked rise in the reported cases of down sydrome in California as well as over the entirety of the US.

There is a big difference between marked rise and 800% rise. Besides if mother's age were a significant factor in autism it would have been found long ago, such correlation is trivial to establish.

The problem with trying to correlate DS and ADS is that DS is known to have a higher occurance in the children of women over age 35 but Autism and other ADS do not have a proven meiotic/genetic link. There are strong indicators for sure, but with ADS patients showing such a large amount of altered genes and a detriment to so many brain interactions and areas, such a link is an example of correlation rather than causation.

This paragraph is completely nonsensical, here's why:

The problem with trying to correlate DS and ADS is that DS is known to have a higher occurance in the children of women over age 35 but Autism and other ADS do not have a proven meiotic/genetic link.

This sentence makes no sense for at least two reasons:
1. There is no problem with correlating the ocurance of autism and Down syndrome, correlation is a statistical tool, basically a function you evaluate for the data, so you can correlate whatever you want.
2. There is no such thing as "meiotic/genetic link", there is genetic link but it has nothing to do with mother's age.
There are strong indicators for sure, ...

Indicators of what? Of link with mothers age? Either there is some link or there isn't saying that there isn't a link but there is 'strong indication' makes no sense as strong indication amounts to some link. As I said before If there was such link it would have been found long ago.
...but with ADS patients showing such a large amount of altered genes and a detriment to so many brain interactions and areas

ADS patients DON'T have any altered genes, this is complete nonsense which proves you have no idea what you are talking about!
such a link is an example of correlation rather than causation.

What link? You said just a moment ago that there is no link only "strong indication" and now you say theres link? Besides this whole sentence is a non sequitur.

In line with this is the fact that DS itself has a 2000% probability increase in women over age 35, from 1 in 100 to 1 in 2000. That is even greater than the 700% increase in ADS noted in California over 20 years.


LOL! Yes and 95000 is even greater then 2000! Seriously you are comparing completely different things, such comparison is completely meaningless!

If the attitude change from stay at home young mother to career first took place in a generation, then the 700% increase is well in line with a social cause rather than an environmental cause.

First of all social cause IS environmental cause, there are only two types of causes genetic and environmental.

Second as I already said it is certainly NOT a mother's age issue as that would be immediately apparent to any researcher.
Velanarris
1 / 5 (1) Jan 09, 2009
Since the authors don't mention the rest of US it implies such a pronounced raise is not present in the other states, or maybe it is just omitted from physorg piece. But even if it were more widespread in it doesn't change much, only the search for the cause should be adapted accordingly.


No, it means it was not in the scope of their research.
From the article: "Hertz-Picciotto and Delwiche correlated the number of cases of autism reported between 1990 and 2006 with birth records and excluded children not born in California. "

The reason why a study like this would focus on alifornia is likely due to the fact that California is the state with the highest birth rate for the country making results found in California a good measure of national trend analysis.

There is a big difference between marked rise and 800% rise. Besides if mother's age were a significant factor in autism it would have been found long ago, such correlation is trivial to establish.
Ok, you've changed the percentage 3 times now. 600%, then 700%, now 800%.

One could say that if autism was linked to environmental factors that it would have been found long ago. Autism is a group of developmental disabilities that don't start at the point of conception like Down Syndrome, so not all aspects necessarily fit. The majority of Autism research has been in post-birth/pre-teen groups in an effort to understand what goes wrong during the child's growth. It is only recently that scientists have started looking at genetic and other correlations.

This paragraph is completely nonsensical, here's why:

The problem with trying to correlate DS and ADS is that DS is known to have a higher occurance in the children of women over age 35 but Autism and other ADS do not have a proven meiotic/genetic link.

This sentence makes no sense for at least two reasons:
1. There is no problem with correlating the ocurance of autism and Down syndrome, correlation is a statistical tool, basically a function you evaluate for the data, so you can correlate whatever you want.
2. There is no such thing as "meiotic/genetic link", there is genetic link but it has nothing to do with mother's age.
Please understnd the subject matter. Down Syndrome is caused by translocation trisomy 21, which is a faiulure during meiosis causing chromosome 21 to become attached to another chromosome during cell division. The end result is 2 chromosome 21's in a single egg or sperm, which, results in a child with 47 instead of the normal 46 chromosomes.


Indicator statement deleted, unnecessary nit picking.
...but with ADS patients showing such a large amount of altered genes and a detriment to so many brain interactions and areas

ADS patients DON'T have any altered genes, this is complete nonsense which proves you have no idea what you are talking about!
Jesus, then this guy better turn in his degrees and tear down his website search engine of genes linked to autism.
http://www.geneticautism.org/


More nit picking deleted.

In line with this is the fact that DS itself has a 2000% probability increase in women over age 35, from 1 in 100 to 1 in 2000. That is even greater than the 700% increase in ADS noted in California over 20 years.


LOL! Yes and 95000 is even greater then 2000! Seriously you are comparing completely different things, such comparison is completely meaningless!
I think you missed statistics class.

Women over 35 have a 1 in 2000 chance.
Women under 35 have a 1 in 100 chance.

Women over 35 have 00 greater chance of having a child with down syndrome.

Now I stated that there's a possibility that autism is also linked to age and said the reason for the p0 increase in autism would be due to a similar mechanic.

for example:

Woman over 35 having an autistic child 1 in 100
Woman under 35 having an autistic child 1 in 5000

If the average child bearing age went up closer to 35 then you'd see a 700% increase...

is that clearer?

If the attitude change from stay at home young mother to career first took place in a generation, then the 700% increase is well in line with a social cause rather than an environmental cause.

First of all social cause IS environmental cause, there are only two types of causes genetic and environmental.

Second as I already said it is certainly NOT a mother's age issue as that would be immediately apparent to any researcher.
A social cause is an environmental cause if you're talking in terms of nature vs. nurture. You are not talking nature vs. nurture. You're trying to state, in absolute terms, that sautism is linked directly to something in the child's environment, and by extension in the mother's environment when she's carrying the child. You then go on to list posions, heavy metals, etc, as the article did.

A social cause would be a cause put onto a person by society. For example the far lower amount of left handed people born prior to 1970. The cause was not genetic, it was a social cause, and in terms of nature vs nurture, an environmental one.
KBK
not rated yet Jan 11, 2009
Get the corporations OUT of the EPA and OUT of the FDA.

Stop the revolving door of where political supporters and lobbying companies involved in the offending industries are allowed to run both of these government offices.

But this, of course, would have to also involve the 'corporation (read :disease or cancer upon the land) riddled Washington' DC to have it's ass completely cleaned out of corporate influence FIRST.

Good luck to you with your US fascism.

The clinical description of fascism is: when corporations and governments collude to disrupt the interest of the public for themselves.

Sound familiar?

When hundreds of Billions (overall $$ at stake) of profit are at stake, the perfect place for corporate greed to slip into in a democratic system that allows for it is: influencing the government. Nothing else delivers such bang for the buck. Thus, your government is completely disease riddled with corporate influence and nothing is done for the common man (for which the government's existence is predicated upon, at least on paper). This, due to the allowance of corporate influence in DC. Kill the corporate influence machine....and get your country back. It really is that simple. Know your target and -- act upon it.
Velanarris
1 / 5 (1) Jan 11, 2009
The clinical description of fascism is: when corporations and governments collude to disrupt the interest of the public for themselves.
No, that's closer to capitalism.

Fascism is when the government sets up a single party system with aim to subdue self interest and encourage nationalistic ideal.

Effectively they would want you to focus on the needs of the nation, and forget your own needs.

Capitalism is when corporation and government get together and do whatever is in their best interests. That's how the money is made in Capitalism, by encouraging greed and self indulgence. It's also one of the few distribution systems that actually generates excess, where communism, socialism, and fascism generate as much as is needed or less. Now that doesn't mean that fascism, communism, and socialism are the same, they're definitiely not, they simply have the same ideal when it comes to resource creation.

How did we get on this topic again?
superhuman
not rated yet Jan 14, 2009
No, it means it was not in the scope of their research.
From the article: "Hertz-Picciotto and Delwiche correlated the number of cases of autism reported between 1990 and 2006 with birth records and excluded children not born in California. "

I know what they correlated, but if you are an autism researcher you know what the situation is in nearby states as well and if it's similar you point it out in your discussion of the results and supply references.

The reason why a study like this would focus on alifornia is likely due to the fact that California is the state with the highest birth rate for the country making results found in California a good measure of national trend analysis.

A state at the extreme is never a good measure of the overall trend.

There is a big difference between marked rise and 800% rise. Besides if mother's age were a significant factor in autism it would have been found long ago, such correlation is trivial to establish.
Ok, you've changed the percentage 3 times now. 600%, then 700%, now 800%.

Did you even read the article? The numbers refer to different things 800% is total increase and 600-700% is the result after correction for population movement and other factors.

One could say that if autism was linked to environmental factors that it would have been found long ago.

Clearly you don't understand the scope of the problem.

Please understnd the subject matter. Down Syndrome is caused by translocation trisomy 21, which is a faiulure during meiosis causing chromosome 21 to become attached to another chromosome during cell division. The end result is 2 chromosome 21's in a single egg or sperm, which, results in a child with 47 instead of the normal 46 chromosomes.

It's you who don't understand the subject matter, there is no such term as "meiotic link" the term I've seen you use on more then one occasion, such changes are called chromosome aberrations, and yes in this specific case it's trisomy of chromosome 21. No one uses the term "meiotic link" for such defects or any defects for that matter.

Indicator statement deleted, unnecessary nit picking.

So, pointing out your nonsensical statements is unnecessary nit picking. LOL!

...but with ADS patients showing such a large amount of altered genes and a detriment to so many brain interactions and areas

ADS patients DON'T have any altered genes, this is complete nonsense which proves you have no idea what you are talking about!
Jesus, then this guy better turn in his degrees and tear down his website search engine of genes linked to autism.
http://www.geneticautism.org/

Seriously, you don't even understand the difference between altered genes and genes linked to something why do you always have to argue things you have no idea about?! Altered genes are mutated genes, cancer patients have altered genes, genes linked to disease are normal genes present in the population, they just make one more prone to develop the disease. Autism patients do NOT show "such large amounts of altered genes", they don't show ANY altered genes.

More nit picking deleted.

I see.

In line with this is the fact that DS itself has a 2000% probability increase in women over age 35, from 1 in 100 to 1 in 2000. That is even greater than the 700% increase in ADS noted in California over 20 years.

LOL! Yes and 95000 is even greater then 2000! Seriously you are comparing completely different things, such comparison is completely meaningless!
I think you missed statistics class.
Women over 35 have a 1 in 2000 chance.
Women under 35 have a 1 in 100 chance.

Women over 35 have 00 greater chance of having a child with down syndrome.

Now I stated that there's a possibility that autism is also linked to age and said the reason for the p0 increase in autism would be due to a similar mechanic.

for example:

Woman over 35 having an autistic child 1 in 100
Woman under 35 having an autistic child 1 in 5000

If the average child bearing age went up closer to 35 then you'd see a 700% increase...

is that clearer?

I know what you mean but it's not how things look IN REALITY. It's important to stay in touch with reality you know?

I looked it up and the increase for women over 35 is 30% not 700% not even 100% it's just 30%!
Source:
http://health.inf...ren.html

So it IS PROVEN that the increase is NOT due to mother's age.
Velanarris
1 / 5 (1) Jan 14, 2009
It is pointless to debate with someone who can't read simple sentences. I'm wasting my time with you.

Enjoy languishing in your ignorance and stubborn inability to reason and understand simple terms.

meiotic link: a link to the process of meiosis.

So it IS PROVEN the the increase is NOT due to a mother's age.


Where?

Math for the percentages is above, as well as the link that shows the statistics, you're changing the scope of the comparison. If you don't understand how percentages work, go back to school.


And by the way, autists have multiple genes that are not the norm, they're a mutation. Hence the term altered genes.
david_42
not rated yet Mar 02, 2009
"Irva Hertz-Picciotto, a professor of environmental and occupational health and epidemiology"
"... We need to even out the funding,"

No professional bias here.