February 6, 2020

Science Reveals Autism and its Causes.


For decades, many parents with autistic children have wanted to know why their child has autism and they wanted something to blame for the condition. This has lead to vaccines being blamed, which many studies have shown is not true, and even other drugs such as antibiotics.

I previously wrote a blog post on this topic, describing the some of the first new findings of genetic reasons, DNA changes, that impact genes encoding for proteins that are important to the normal function of neurons (neural cells) in our brains. This has come about largely because of our ability to now completely read the entire genomic DNA sequence of a patient. Children with autism, and also the genomic DNA sequences of their parents.

This is possible because, for just hundreds of dollars, we can sequence 6-billion bases of anyone's genomic DNA. (3-billion DNA bases from Mom and 3-billion from Dad.) Studies of hundreds of volunteer Families have revealed that autistic children often have defective genes required for neuron communication, and also that their DNA base changes are often not inherited directly from their parents. The DNA base change has occurred as a typical DNA error during the production of sperm or oocytes or during fertilization or very early in the embryo's growth. Thus these changes are long before immunization and they are changes to DNA sequence for genes that happen to be important for neurons to communicate and connect in the brain.

This insight into autism is important, because just as for many other diseases with genetic causes, like Retinitis Pigmentosa (blinding eye diseases), different persons with autism can have different genes with different unique changes to the DNA. These differences can mean that different kinds of treatments may need to be developed for different individuals. There will not be one drug, therapy or diet that improves the condition in every autistic child. It also means that some autism will require dramatic interventions to correct the problem in neural functions. Interventions like gene therapy.

One thing is certain, scientific investigation often first reveals the causes of what are otherwise mysterious medical conditions. Then we at least understand reasons and causes, even if we do not have the cure readily at hand. What we do have is the why, and only then can we intelligently start to look for ways to fix what may be broken. Vaccinations are not what makes autism. The more time one spends insisting that they do, the more time we waste by not dealing the the causes of autism that are being revealed in our own DNA.

We must live to some extent with the reality that we are imperfect organisms. Life arose and survives on this planet despite some pretty slim odds, and we humans are not perfect. Thousands and thousands of humans have had their genomic DNA sequenced and compared now by 2018 and we understand much of what was mysterious just before 1999. Before 1999, geneticists were guessing we humans would have between 150,000 to 500,000 genes. Now we know we only have just over 20,000 genes. Maize (corn) has a genome of over 150,000 genes! Actually getting our genome sequenced revealed the reality, not the guess, and improved our understanding of how important the process is of making slight variations of proteins from one gene to produce a walking human. But just 20,000 genes. DNA sequencing is now much easier, and we can sequence your 6-billion bases of DNA in a single day on a machine.

Genetic research has not stopped and a large worldwide effort has recently reported the results from the genomic (DNA-sequencing) analysis of over 35,000 persons, of which over 11,000 have an ASD (Autism Spectrum Disorder).  "Large-Scale Exome Sequencing Study Implicates Both Developmental and Functional Changes in the Neurobiology of Autism." a report produced by over 140 collaborators and published in the journal Cell:


This study was funded by the US National Institutes of Health (NIH) and managed by the international Autism Sequencing Consortium (ASC).  Its findings have increased the number of gene variants to 102 genes that are now associated with an increased risk of developing Autism Spectrum Disorders. 53 of the 102 are mostly linked to ASD and not linked to other forms of intellectual impairment or developmental delay.

It turns out that all of us humans have mutations and imperfections in our genome. As a matter of fact, we all have about 12 bad copies of a gene that is so important we would not be living if we did not have one other good copy from our other parent. Little aches and pains that we suffer while others may not, on average, could be signs of such imperfections we have that are survivable. So very human. We all have imperfections. Some have more consequence than others, but they are no one's fault. They are not the result of anyone's sins. It's just being human. So in the end science tends to reveal our humanity. Sometimes that is scary, but mostly knowledge can be useful. Knowing what causes autism is necessary before anyone can figure out how to reduce or even fix it.

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