How does autism prediction work?

This podcast provides updates on studies that help with prediction of an autism diagnosis – which is important for preparing for the future and for intervening early. First, a study that uses environmental factors to create an equation for the probability of a diagnosis following a combination of of non-genetic factors only which does a fairly good, but not perfect, job at predicting a diagnosis. Second, a study that looks at the accuracy of a machine that predicts autism from eye gaze as early as 9 months of age and with only a 2 minute test. This one wasn’t as accurate as the one that takes longer and tests older kids, but it’s a first step. No ONE thing does a perfect job at predicting a diagnosis – it’s going to be a combination of things, tested over time and multiple times that will be most helpful at predicting a diagnosis. Both studies are open access!

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10904522/pdf/fpsyt-15-1291356.pdf

https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/38429348/

Resilience and heterogeneity in ASD

Everyone knows that every person with autism has their own unique strengths and challenges. Autism is heritable, and there are over 100 genes associated with autism. There are also an unknown number of environmental factors influencing outcome, so the heterogeneity is not necessarily surprising. But why would two people with the same genetic mutation have variable outcomes? Researchers led by the Institut Pasteur in France looked at the range of outcomes in people with a rare genetic mutation associated with autism, focusing on those without an autism diagnosis. This week’s podcast is an interview with the lead author of the paper, Thomas Rolland, PhD from France. The presence of the variants in those without ASD were associated with lowered cognitive ability, education level and employment status. The bottom line of these finds are that genes affect proteins which form the brain and control brain function. However, there are multiple factors that influence outcome. Some of them may be sex or gender, prenatal exposures. It’s not just one thing, there are many things influencing an autism diagnosis.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10353945/pdf/41591_2023_Article_2408.pdf

A potential biomarker to AID, not MAKE, a diagnosis

The media has just called another biological marker a “diagnostic test”, when in this case, it was always intended to be an aid, not a test itself. It involves using baby hair strands to look a variation in metabolism of certain chemical elements across time. Remarkably, it showed similar results in autistic children in Japan, the US and Sweden. It’s not ready to be used as a diagnostic test, so what is it supposed to do? Listen to an interview with the inventor and researcher, Dr. Manish Arora from The Icahn School of Medicine at Mt. Sinai School here.

The full article (open access) can be found here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9740182/

Genetic confounding plus organoids

You heard it in the news this week, and we discuss it on this week’s ASF podcast. Can you make little brains in a dish then make them better by providing them a real structured live neural environment? Can these organoids integrate with a live brain and be functional in vivo? The answers are: yes! Learn more from a new study published this week. Also, what the h**l is genetic confounding and how can it address many of the controversies of genetic vs. the environment? Sometimes genes that predispose to a disorder also predispose to environmental factors leading to that disorder. There is always room for both. Here are the links I promised:

https://www.fhi.no/en/studies/moba/

https://pubmed.ncbi.nlm.nih.gov/35793100/

https://www.nature.com/articles/s41586-022-05277-w

What is the problem getting to the bottom of biomarkers and gene x environment interactions

Outcome measures for clinical trials and understanding and determining gene x environment interactions have been two (of many) challenging questions for scientists. In the first study, we explain a new study that looks at the feasibility of three potential biomarkers that have the potential to look at presence of a diagnosis as well as effectiveness of an intervention. In the second half, we describe some new research that shows novel approaches to better understand the presence of an environmental factor with genetic influences, or a new method to describe them in different communities. You can read the studies by clicking below:

https://pubmed.ncbi.nlm.nih.gov/36000217/

https://pubmed.ncbi.nlm.nih.gov/35974006/

https://pubmed.ncbi.nlm.nih.gov/35992618/

Environmental factors as both causes and interventions?

Environmental exposures, including toxic chemicals, can contribute to the causes of ASD. But how do other environmental factors, like behavioral supports, work in the brain to improve behaviors associated with ASD? For this, you need a broad interpretation of the term “environmental” and an animal model so you can see the mechanism involved. Studies show while environmental factors can contribute, they can also provide modifications in cellular and molecular function which support learning and improved developmental trajectory. Finally, on a different topic, are autistic adults more likely to be involved in a crime compared to other groups? No, they are not, but there are factors which affect the risk of being involved with the criminal justice system, at least in the UK. Read more in the studies below.

https://pubmed.ncbi.nlm.nih.gov/34972219/

https://pubmed.ncbi.nlm.nih.gov/35259351/

https://pubmed.ncbi.nlm.nih.gov/35261275/

A new ways for the environment to affect genetic expression

You have maybe heard about how environmental exposures after conception or birth may affect genetic expression and then risk of developing autism. But what research has been done to look at preconceptional exposures, presumably exposures that affect the cells that then give rise to sperm and eggs? Turns out they are susceptible to some environmental exposure too, which could lead to a change in the way genes are expressed in the embryo, the fetus, and then the child. Want to know more? Jill Escher just published a study with scientific colleagues about this hypothesis and she explains it in this week’s podcast.

https://pubmed.ncbi.nlm.nih.gov/34596807/

What causes autism? Genetics or the Environment? Or maybe both?

Is it genes or is it the environment? or is it a combination? This question has plagued researchers and scientists and caused a lot of confusion in families about what caused their own or their child’s ASD. This week we review the mechanisms by which de-novo mutations could be the work of gene x environment interactions, and share new evidence of how SSRI’s do or don’t contribute to ASD through gene x environment interactions. We also want to recognize the valuable work of scientist Li-Ching Lee to these efforts. Dr. Lee recently passed away but will be sorely missed.

https://pubmed.ncbi.nlm.nih.gov/34002022/

https://pubmed.ncbi.nlm.nih.gov/34116791/

What is the point of genetic testing?

If only 10% of people with ASD have a known genetic mutation associated with autism, what is the point? Why bother? This week we discuss why it is important for that 10%, what the benefits are, and how genetic testing may help the other 90% as well.

https://www.sciencedirect.com/science/article/pii/S0002929720301130

https://pediatrics.aappublications.org/content/146/4/e20193211

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2869000/

Beyond what scientists already know about environmental factors

This week the ASF Podcast explores two ways to better understand the environmental influences in ASD diagnosis: 1. through potential cost savings of avoided cases of ASD due to reduced air pollution and 2. by studying pre-conception exposures going back as far as the grandparents exposure. These two concepts do not prove any one thing, including one environmental factor, causes ASD, however, using these approaches may improve understanding of ASD and allow for legislation that improves many health outcomes in children. Below are the two references:

https://pubmed.ncbi.nlm.nih.gov/32749866/

https://pubmed.ncbi.nlm.nih.gov/32704384/