Neurodiversity was introduced to my vocabulary by Dr. Jason Howitt during his QBI seminar: TARGETING AUTISM USING MECHANISM BASED THERAPEUTICS – CAN WE CURE AUTISM AND DO WE WANT TO?
He began by explaining that autism is a “disorder across a spectrum, not a disease”. This means that those who are on the high functioning end of the scale may feel quite strongly that the different way their brains functions is to be celebrated, not denigrated. Howitt recommended Steve Silberman’s fascinating book on the subject NEURO TRIBES: The Legacy of Autism and the Future of Neurodiversity. Of course when I spoke to my high-schooler about the topic she was already in the know about the meaning of neurodiversity and the rainbow infinity symbol. Families and friends of people with ASD feel that society should be more accepting of diversity and forthcoming with support regardless of where they sit on the spectrum. Nonetheless, there is no doubt that living with ASD can be challenging and heartbreaking. I remember with dismay the Insight (SBS) program about ASD. There was testimony from a single mum who had nurtured her son to adolescence, which meant that physically who could get the better of her when he was enraged. In despair she came to the conclusion that life was too difficult and planned to end both their lives with a drug overdose. They were discovered - she was resuscitated, but sadly her son died. So DO WE WANT TO CURE AUTISM is a complex question.
The rate of ASD in the U.S. is one in 68, that sharpens to one in 40 for boys. There are over 1000 genes linked to ASD, 40% of ASD is unaccountable genetically so how can treatments be tested. Howitt’s lab has narrowed their focus to ASD with macrocephaly (enlarged brain). There is one gene linked closely to ASD with macrocephaly is PTEN. PTEN is usually a tumour supressing protein, but when it mutates it is closely associated with cancer In the lab they have created a neurodevelopmental mouse model of PTEN-ASD, that allows them to test with drug treatments.
From cancer research it is known that Rapamycin is a drug that targets PTEN, it limits tumour growth in the brain so they started trialling Rapamycin as a treatment. As the trials continued Drug 2 was tested alone and then in combination with Rapamycin. It seems that daily low doses of the combined drugs is able to show a decrease in brain size – to change synaptic plasticity and show a decrease in synaptic growth without effecting the *phenotype. The lab predicts that these drugs would only need to be administered druing the critical development stage of the brain up to the age of five. Using drugs that are already FDA approved in the trials , means the process of becoming an accepted treatment path can be sped up. The next stage is collecting ^fibroblasts from ten confirmed PTEN-ASD patients from Royal Childrens Hospital Mebourne – these cells will be tested with the drug treatments from the mouse model.
Every time I leave these seminars my brain is humming with fascinating new information. The way scientists continue to come up with new theories and design research to prove these theories is a marvel. Also though, quite challenging, during the Q&A session, Howitt admitted that it is difficult to get high numbers of the PTEN mice to trial as they are often eaten by their mums. Is that a better excuse than the dog ate my homework?
*the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.
^ A fibroblast is a type of cell that synthesizes the extracellular matrix and collagen, the structural framework (stroma) for animal tissues, and plays a critical role in wound healing. Fibroblasts are the most common cells of connective tissue in animals.