Posted on

Ribbit…Ribbit… frogs are the new mouse of ASD research

Podcast: Play in new window | Download

Subscribe: RSS

You’ve heard a lot about CRISPR technology to manipulate gene expression. But what have scientists actually learned? Well, the cells in which DNA is manipulated could come from different animal models, including frogs and mice. These model systems are used to track brain development, sex differences, and the downstream effects of convergence of genetic manipulations of autism relevant genes on brain cells. They can be used, as one study demonstrated, to examine protective or resilience factors in the brain. This week we talk to Helen Willsey, PhD, at UCSF to hear about her research about manipulating genes in frog eggs and what it says about the female protective effect.

https://pubmed.ncbi.nlm.nih.gov/33497602/

https://pubmed.ncbi.nlm.nih.gov/33243861/

Posted on

A new type of genetic mutation in ASD

Podcast: Play in new window | Download

Subscribe: RSS

On today’s ASF podcast, ASF funded researcher Ileena Mitra from the lab of Dr. Melissa Gymrek at UCSD will explain a new type of “de novo” genetic mutation. Those are those spontaneous mutation that happen in kids with ASD but not parents or family members. So where did they come from? Well, this study looks at a mutation that affects tandem repeats, which are those repeating DNA sequences: CGG CGG CGG CGG. A newly built bioinformatics platform showed that these mutations may account for 1.6% of simplex (one person in the family is affected). Likely we are going to hear more about these types of mutations in ASD, so listen to the scientist explain the science herself!

https://www.nature.com/articles/s41586-020-03078-7

Posted on

What is the point of genetic testing?

Podcast: Play in new window | Download

Subscribe: RSS

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/

Posted on

Psychiatric decompensation and autism: Two words you never want to hear together

Podcast: Play in new window | Download

Subscribe: RSS

A series of three scientific articles explore the link between the onset of psychiatric symptoms in adolescence in people with Phelan McDermid Syndrome, or PMS.  PMS is caused by a mutation in the SHANK3 gene, leading to a wide range of medical, behavioral and intellectual challenges, as well as autism spectrum disorder.  Scientists used a broad literature review as well as the PMS patient registry to better describe what was going on, and a group at Duke compiled a case series of girls affected that were responsive to treatment.  While so far this decompensation as a result of onset of psychiatric illness has only been documented in PMS, families across the spectrum should be aware so they can seek immediate help for their child if they see similar symptoms.

https://www.ncbi.nlm.nih.gov/pubmed/32050889

https://www.ncbi.nlm.nih.gov/pubmed/31879555

https://www.ncbi.nlm.nih.gov/pubmed/32015180

Posted on

Genes genes all in an order, the ones you have, the greater risk of disorder

Podcast: Play in new window | Download

Subscribe: RSS

This week, a special focus on genetics:  what type, where do they come from, what do these genes do and how do they influence risk of a wide array of psychiatric issues including autism.  The results come from the largest study to date of people with autism as well as those with ADHD, bipolar disorder and schizophrenia.  It’s also the largest study of the Female Protective Effect so far.  Even if genetics does not explain everything about ASD, genetics is important and you deserve to know why.  Below is a graphical abstract of what they found:

 

 

https://www.cell.com/action/showPdf?pii=S0092-8674%2819%2931398-4

https://www.ncbi.nlm.nih.gov/pubmed/31835028

 

Posted on

Environmental factors: the forgotten stepchild of autism spectrum disorders

Podcast: Play in new window | Download

Subscribe: RSS

When people hear the word “heritability” in mathematical estimates, they automatically think “just genetics”.  That isn’t true, and this week epidemiologist Brian Lee from Drexel talks us through his SpectrumNews viewpoint about what heritability actually is and why there is room for environment.  Also this week, twin studies, which have traditionally used the word heritability to distinguish genetic vs. environmental interactions, are studied in a new light.  This one shows that severity and differences of autism across the spectrum in identical twins are caused by environmental differences – not just genetics.

https://www.ncbi.nlm.nih.gov/pubmed/31853901

Posted on

What sperm tells scientists about the origins of ASD

Podcast: Play in new window | Download

Subscribe: RSS

Does autism begin at a diagnosis, or before a diagnosis?  How early do genetics influence outcome?  This podcast explores a new angle to this question using studies in sperm.  One type of major ASD relevant mutation is de-novo mutations, meaning they are seen in the person with ASD but neither biological parent.  So where do they come from?  They may come from germ cells of the embryo of the parent, which forms the sperm and the egg.  Researchers from UCSD looked at mutations in sperm vs. blood in fathers of those with de-novo mutations and found an enrichment of genetic mutations in sperm.  This means the window of susceptibility can include not just things that happen at conception, but before conception.  Below is a graphic taken from a commentary of this study in Nature by Eric Morrow which may be helpful.

 

Posted on

The newest on using genes to predict later diagnosis and those immune blebs in the brain

Podcast: Play in new window | Download

Subscribe: RSS

Hot off the press:  new data from a collaboration between the BSRC and geneticists in Canada demonstrate the utility of genetics to predict either ASD or atypical development in infant siblings of children already with a diagnosis.  Researchers have been trying to develop more precise biological mechanisms to make predictions in these infants, because they have a 15x greater chance of having a diagnosis, they can’t afford a “wait and see” approach.  Also, while genetics had originally been thought to be irrelevant to some brain pathology in ASD, it’s now been shown possible that it contributes to the immune hyper activation in the brain.  This week, Dr. Matt Anderson from the Autism BrainNet describes “blebs” in the cells of the brain caused by t-lymphocytes.  What causes them?  Genes?  something else?  Thank you to Dr. Anderson for joining in this podcast to explain.

https://www.ncbi.nlm.nih.gov/pubmed/31801954

https://www.ncbi.nlm.nih.gov/pubmed/31591744

 

Posted on

Praise for genetic testing in ASD

Podcast: Play in new window | Download

Subscribe: RSS

Genetic testing for autism spectrum disorders is not just about finding the gene.  So many genes have been found that genetic testing allows families who have a rare genetic disorder to find each other, support one another, raise money for research and train physicians to better help their community.  While genetic testing isn’t always pushed, it should be.  Autism Science Foundation has organized an initiative called AGENDA (www.alliancegenda.org) to bring together rare diseases associated with ASD.  This is important in moving from discovery to development faster.

https://www.ncbi.nlm.nih.gov/pubmed/31542846

https://www.ncbi.nlm.nih.gov/pubmed/31548702

 

Posted on

SPARK it up

Podcast: Play in new window | Download

Subscribe: RSS

You may have heard of SPARK, it is the largest genetics research project in autism spectrum disorders.  But have they found anything?  Yes!  Pam Feliciano of SPARK discusses what the project is, what a pilot study has found, and how the results might help families with ASD.  In addition, a different but complementary study identified new genes associated with autism.  Given that one of them is a target of environmental factors, it’s time to spark up studies looking at gene x environment interactions as well.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6707204/

https://escholarship.org/uc/item/36f811zq

https://www.tandfonline.com/doi/full/10.1080/15592294.2019.1656158