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The genetic influence on autism is complex, with research suggesting that a combination of genes work together to render an individual susceptible. One way to address this complexity is for researchers to investigate a large collection of families with affected individuals in order to understand which genes likely contribute to autism risk.
In order to better describe the genetic influences in autism spectrum disorder, in 2004 Autism Speaks provided support to the Autism Genome Project. This project brought together 170 of the world’s leading researchers to collaborate and build the largest dataset of DNA from families affected by autism. The researchers, who represented over 50 institutions worldwide, assembled a database of over 1400 families, 1168 of which contained at least two members affected with autism. This set represents a much greater sample size than has ever been studied previously.
Combining the expertise of these researchers, this project is the largest collaboration in the world to study the genetics of autism. Together, they used standardized cutting-edge and state-of-the-art technologies to detect the genes which are associated with this disorder, and then pooled their results across sites so that meaningful conclusions could be made. (Learn more about results from the first phase of the project).
The methods used by the AGP involved studying both the entire genome (all 23 pairs of chromosomes) as well as regions of interest within these chromosomes. A chromosome is an organized set of DNA which contains the genetic code of an individual. Each person has different DNA sequence and corresponding gene function and protein expression in the brain. Different DNA codes are part of what makes each of us different.
The investigators searched for clues in the pooled genetic database using a variety of techniques and by conducting linkage analysis. Linkage analysis is a technique that helps identify where genes are located in the human genome. It refers to the tendency of genetic markers, which are segments of DNA inherited from a person’s parents, including those that may be associated with diseases, to be located together on a chromosome.
In this study, linkage analysis of individuals affected with autism yielded many areas of interest, including chromosome 11, specifically region 11p12-p13. Therefore, it is likely that these chromosomal regions harbor autism susceptibility genes.
Another way to address the genetic complexity of autism and to further define and describe genetic mutations is examination of copy number variations, or CNVs. CNVs are submicroscopic duplication, deletions, or rearrangements of genetic materials in the DNA. They can vary in length and position on the chromosome. Therefore, the presence of copy number variations in the DNA sequence has the potential to disrupt gene function and contribute to the disorder. Examination of copy number variation is sometimes missed in surveys or experiments of the genetic determinants of disease and the contribution of CNV’s to some diseases is yet unknown.
The CNV analysis allowed researchers to make additional observations relevant to the genetics of autism. While some of the CNV’s found were not related to autism spectrum disorder, others were found in siblings with autism spectrum disorder. Many of these specific copy number variations occurred in the same area of the chromosome. In addition, several of these CNVs were increased copy numbers located in chromosome 15 and were maternally inherited. While they add to the complexity of the data, these specific CNVs are enormously helpful in determining the nature of the genetic influence of autism.
As an example, a de novo CNV, that is a variation that wasn’t transmitted by either parent, was found on a region of chromosome 2 called “2p16” in a pair of affected siblings. This CNV was a deletion in the gene that codes for a protein called neurexin or NRXN1. NRXN1 interacts with neuroligins, a class of cell adhesion molecules, or proteins which control how brain cells connect with each other. This neurexin-neuroligin interaction is important because this relationship guides axon signaling and mapping. That is, this interaction helps direct neurons to their proper target during development, and forms specific signaling pathways in the brain.
Changes in the expression of neuroligin have been previously associated with an increased risk of ASD and mental retardation. Moreover, the neurexin-neuroligin link is important for the functioning of synapses which control the release of a neurotransmitter called glutamate. Many scientists theorize aberrant glutamate function is involved in ASD.
Of the 168 genes involved in glutamate synthesis and functioning, several fall within linkage regions found in this study. Two in particular, SCL1A1, which maps to 9p24.2, and SCL1A2, which maps to 11q13-12, are especially promising candidates for future study.
The innovative combination of linkage and CNV analyses on the largest-ever collected cohort of families affected with autism offers new avenues of research to identify the genetic components of ASD. This research finding supports the influence of genetics on autism spectrum disorders and lays the foundation for later studies which will investigate the role of the environment with this genetic susceptibility. It also advances the possibility of biological diagnosis and of improved treatments targeted at specific symptoms.
Autistic people have fought the inclusion of ABA in therapy for us since before Autism Speaks, and other non-Autistic-led autism organizations, started lobbying legislation to get it covered by insurances and Medicaid.
ABA is a myth originally sold to parents that it would keep their Autistic child out of an institution. Today, parents are told that with early intervention therapy their child will either be less Autistic or no longer Autistic by elementary school, and can be mainstreamed in typical education classes. ABA is very expensive to pay out of pocket. Essentially, Autism Speaks has justified the big price tag up front will offset the overall burden on resources for an Autistic’s lifetime. The recommendation for this therapy is 40 hours a week for children and toddlers.
The original study that showed the success rate of ABA to be at 50% has never been replicated. In fact, the study of ABA by United States Department of Defense was denounced as a failure. Not just once, but multiple times. Simply stated: ABA doesn’t work. In study after repeated study: ABA (conversion therapy) doesn’t work.
What more recent studies do show: Autistics who experienced ABA therapy are at high risk to develop PTSD and other lifelong trauma-related conditions. Historically, the autism organizations promoting ABA as a cure or solution have silenced Autistic advocates’ opposition. ABA is also known as gay conversion therapy.
The ‘cure’ for Autistics not born yet is the prevention of birth.
The ‘cure’ is a choice to terminate a pregnancy based on ‘autism risk.’ The cure is abortion. This is the same ‘cure’ society has for Down Syndrome.
This is eugenics 2021. Instead of killing Autistics and disabled children in gas chambers or ‘mercy killings’ like in Aktion T4, it’ll happen at the doctor’s office, quietly, one Autistic baby at a time. Different approaches yes, but still eugenics and the extinction of an entire minority group of people.
Fact: You can’t cure Autistics from being Autistic.
Fact: You can’t recover an Autistic from being Autistic.
Fact: You can groom an Autistic to mask and hide their traits. Somewhat. … however, this comes at the expense of the Autistic child, promotes Autistic Burnout (this should not be confused with typical burnout, Autistic Burnout can kill Autistics), and places the Autistic child at high risk for PTSD and other lifelong trauma-related conditions.
[Note: Autism is NOT a disease, but a neurodevelopmental difference and disability.]
Fact: Vaccines Do Not Cause Autism.