Dear Hasna,

Autism is still a dramatic disease whose causes are not completely known. However, there a broad consensus that autism has biological roots, but it also depends on the environment. Is seems that a non-nurture enviroment is also responsible for the appearance of that dramatic mental disease.

KInd regards,

Orlando

The aetiological basis of autism is predominantly genetic, and the apparent rise in diagnosis has more to do with increased awareness of the condition and changes in the diagnostic criteria. Nevertheless, while mutations in some genes are strongly implicated in autism, most associated variants confer modest increases in risk.

These genetic variants of small effect sizes can have a significant impact when present in certain combinations, or even lower the threshold of one acquiring the condition with exposure to environmental risk factors.

The answer to what causes autism is unlikely to reside solely in genetics. Recent studies suggest that environmental factors can cause autism, but this is most likely to occur in utero (during pregnancy). This is important because some parents are concerned that things such as high pollution or vaccines cause autism postpartum.

Regardless, the heritability of autism is estimated to be more than 90%. This means that more than 90% of the cause of autism is due to genetics.

The bottom line is that whatever the cause of autism may be – genetic or environmental – it is likely to take effect during foetal development. Thus, a person with autism is born with autism.

Clinical data from recent years indicate the obvious genetic cause of autism, but do not exclude epigenetic factors. The latter are more likely than those of the environment because, under the same conditions in the environment, autism affects only a small number of them. The strongest evidence in favor of the genetic origin of autism is the very early signs of neurodevelopmental disorder and neurophysiological evidence of atypical brain function. I also think that the child is born with autism.

"The strongest evidence in favor of the genetic origin of autism is the very early signs of neurodevelopmental disorder and neurophysiological evidence of atypical brain function."

What is the evidence that abnormal brain function is the cause and not the result of autistic symptoms, from sensory disorders for example?

Every mental function as well as that of the sensory organs is a natural consequence of the functioning of certain brain regions. When their early development is delayed or flowing through atypical mechanisms, we see various symptoms that are always the result of deficiencies in the brain substrate. There are no mental problems that are in some way unrelated to brain development, although sometimes proving them difficult.

Epigenetic for sure because purely genetic basis is lacking due to heterogeneity in its clinical picture. But probably genetic studies need a paradigm shift to understand the genetics behind psychiatric disorders.

I agree. In my opinion, in recent years, there have been interesting new discoveries - changes in major blood factors, hormonal factors in the early years, abnormal brain hemispheres, etc., have been identified that speak of a possible combination for many reasons.

Dear Orlando,

I agree with your conclusions.

There is a not widely known genetically programmed deadline discovered by Paul Flechsig in the 1920's that the myelination of the neocortex verbal areas is genetically delayed until the age of about 7, which may explain why children in multiethnic families usually easily learn more than one mother tongue in youth to similar mastery levels, and also why children who have not mastered reading and writing of their mother tongue to autonomy by this age experiment increased levels of difficulty in completing later this training as well as other verbal trainings.

This discovery by Flechsig seems to directly correlate with Chauchard’s observation that the density of the interconnected network being built in the verbal areas during articulated language acquisition is much denser in those of children who complete this learning before the age of 7 than in those of children who did not complete this learning in a timely manner, which seems to also directly correlate with the observation made by Dolores Durkin that all children who had learned to read before the age of 7 dominated markedly in all learning tasks over the entire period of their primary schooling in California with none of the children who had learned to read past this age being able to catch up with them.

This seems to hint at the possibility that if this genetically programmed myelination was accidentally triggered sooner in some children's lives, possibly due to environmental factors, these children would simply be afflicted with the same higher level of difficulty from a younger age in further learning articulated language, that affects those who do not complete this training to complete autonomy before the normal myelination triggering age of about 7, unfortunately in their cases, before they master language to a level sufficient to even become able to verbally express their needs, that can possibly be related to the high levels of related frustration that can be imagined, and which is observed in these children.

References:

Flechsig, P., (1920) Anatomie des Menschlichen Gehirns und Rückenmarks auf Myelogenetischen Grundlage, Leipzig, Thienne, Germany.

Chauchard, P., (1960) Le cerveau et la conscience, Les éditions du Seuil, France.

Dodson, F., (1971) How to Parent. USA (where the Dolores Durkin field research is mentioned).

https://www.omicsonline.org/open-access/intelligence-and-early-mastery-of-the-reading-skill-2155-6180-1000327.pdf

Unfortunately for the general progress of science, the first 2 references never were translated to English.

Best Regards, André

I think that the causes of autism should not be strictly differentiated. In some cases, genetic factors are influenced by environmental factors, others are related to hereditary burden, and so on. I think this is an explanation for the wide variety of cases, forms and degrees of autism, which makes it very difficult to diagnose, especially the choice of therapy. Therefore it is said that the rule "one disease - one reason" does not apply here. It is transformed into "one disease - many causes".

Dear Neli,

I simply submit that this possibility never was investigated.

Best Regards, André

@ Hasna Mohaus

Please take a look at this useful RG link.

Article Epigenetic Effect of Environmental Factors on Autism Spectru...

Thanks!

Following

Hello,

No specific “cause” has been identified. It is likely it is a combination of factors from genes, the environment, and other individual factors. I attached some recent research:

Hodges, H., Fealko, C., & Soares, N. (2020). Autism spectrum disorder: definition, epidemiology, causes, and clinical evaluation. Translational pediatrics, 9(Suppl 1), S55.

Heres a recent report on perceived causes in the United States:

Castillo, A., Cohen, S. R., Miguel, J., & Warstadt, M. F. (2020). Perceptions of causes and common beliefs of autism spectrum disorder in the US. Research in Autism Spectrum Disorders, 70, 101472.

As the previous answers explained, there is still no complete knowledge about the cause or causes of autism, as:

- Researchers agree developmental disabilities such as autism are mainly because of brain disorders, which leads to vital symptoms in neurology, not psychiatry.

- Researchers at the Autism Study Center in Princeton-New Jersey are assumed that ASD may result from an unknown gene affected by unknown damage or brain tissue damage resulted from an environment that leads to distortions in the neurotransmitters.

- Federal Center for Disease Control is assumed that there is no single cause for this disorder but results from overlapping several reasons, which have not been identified.

References:

- E. London and R. Etzel, “The Environment as an Etiologic Factor in Autism: A New Direction for Research,” The National Institute of Environmental Health Sciences, vol. 108, pp. 401-404, 2000. [Online]. Available: DOI: 10.2307/3454527.

- Center for Disease Control and Prevention, “What is Autism Spectrum Disorder ?,” Mar 25, 2020. Accessed on: May 10, 2020. [Online]. Available: https://www.cdc.gov/ncbddd/autism/facts.html