Bogus Study: Cutting Edge: Critical Roles For Microbiota-Mediated Regulation of the Immune System in Prenatal Immune Activation Model of Autism

 Over the past few decades, scientist have not stopped trying to find the cause of autism. They have been ignoring the autistic community's plea that we don't want to be cured, we just want accommodations so we can be the best we can be. 

Mice Predicting Autism? 

Recently there was a study at the University of Virginia put out in The Journal of Immunology connected the pregnant mother's microbiome (bacteria in the gut) to autism. They took the idea that a large part of the immune system is in the intestines, which is true and that there are markers in the gut whether or not a person may develop certain autoimmune conditions such as lupus or type one diabetes. They thought that the microbiome would predispose a person to autism, a neurological difference, which makes ZERO sense. They rationalize it by saying "recent studies suggest autism is often associated with dysregulated immune responses and altered microbiota composition. This has led to growing speculation about potential roles for hyperactive immune responses and the microbiome in autism." We would love to see these studies that they don't cite. 

How they Determine if Mice are "Autistic"

They tested mice that exhibit "autistic traits" and said they are autistic. Animals cannot be autistic. There is no veterinary diagnosis of autism. The genetics and brain structure and function differs too much from humans to make any sense. They determined which mice were "autistic" by conducting behavior testing in daylight. They also removed the male babies and they started to cry. They seemed to count that as an autistic meltdown. No, the babies were in distress from being taking away from their mother. 

The "symptoms" they used to determine if the mice were autistic:

  • social preference abnormalities
  • communicative differences

How They Tested the Mice Feces

They said they found a link between gut microbiome and autism in animal studies. They say it's the pregnant person who is carrying a fetus microbiome, not the baby's microbiome. The mice were housed and behavior was conducted in pathogen free conditions under a standard 12 hour light and dark cycle with temperature control. Mice matched fro sex and age were randomly assigned into experimental groups. 

The fecal samples that were tested from the mother mice and baby mice were collected three times per week from mice that were 3-6 weeks old for 2 weeks. There was a DNA test performed on the fecal samples. As they tested the fecal samples, if the mom and pup had the same biome, that was considered a link. There are only so many microbiomes out there. As we always say, correlation does not equal causation. 

Fecal Transplanting

They actually did fecal transplants on these mice. This is surprising considering how Jason Klop was in the news for doing this to human children and under investigation in Canada. This has never been proven to "treat" autism and is scientifically irrelevant. 



Microbiome Does Not Cross the Placenta

One problem I had with this study is that in order for the microbiome of the mother to effect the fetus is that it has to cross the placenta. The placenta is the only way that the mother has a link to the fetus. Nutrients, blood pass through the placenta. Waste from the fetus goes into the amniotic fluid. 

A study was published in the American Journal of Obstretics and Gynecology called No Evidence for Placental Microbiome in Human Pregnancies at Term. This study was to investigate the existence and origins of placental microbiome. 

This study was a cross sectional study comparing samples from 2 group software full term births. 50 pregnant people not in labor with an elective cesarean and 26 with natural deliveries. The comparisons were performed using amino acid (polymerase) reaction amplification and DNA sequencing techniques and bacterial cultures. 

There were no significant differences in the characteristics between the pregnant people who had c-sections and who delivered naturally. There were measurements of bacterial content in all 3 placental layers did not show any significant difference among any of the sample types and the negative controls. 

They found no evidence to support of placental microbiome. 

Sources:

https://www.iflscience.com/health-and-medicine/autism-could-be-linked-to-mothers-gut-microbiome/

https://www.jimmunol.org/content/jimmunol/early/2018/06/29/jimmunol.1701755.full.pdf

https://www.sciencedirect.com/science/article/pii/S0002937820309844

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