Folate receptor autoantibodies are prevalent in children diagnosed with autism spectrum disorder, their normal siblings and parents.
Folate receptor antibodies travel in autism families—screen the whole household when one member tests positive.
01Research in Context
What this study did
Quadros et al. (2018) drew blood from children with autism, their brothers and sisters, and their parents.
They also drew blood from unrelated people who had no autism in the family.
The lab looked for auto-antibodies that block the folate receptor.
What they found
The antibodies showed up far more often in the autism families than in the control families.
Siblings and parents, even those without autism, often carried the same antibody.
This pattern hints the antibody is a shared family trait, not just an autism trait.
How this fits with other research
Pu et al. (2013) pooled eight studies and found that a common MTHFR gene variant raises autism risk, especially in countries that do not fortify food with folic acid.
The two papers point to the same pathway: trouble moving folate raises autism risk.
Aldred et al. (2003) and Martens et al. (1989) used the same family-plus-control design and found that other biochemical markers—amino acids and serotonin—also cluster in autism families.
Together these studies show that metabolic quirks, not just genes for autism, run in families.
Why it matters
If you serve a child who tests positive for folate receptor antibodies, ask the lab about testing parents and siblings.
Finding the antibody in the family can guide folate supplementation choices and may explain language or attention issues in siblings who do not have autism.
It also gives you a clear, biology-based talking point when families ask, “Why us?”
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02At a glance
03Original abstract
UNLABELLED: Folate deficiency can affect fetal and neonatal brain development Considering the reported association of Folate receptor alpha (FRα) autoantibodies (Abs) with autism and developmental disorders, we sought to confirm this in families of 82 children with ASD, 53 unaffected siblings, 65 fathers, and 70 mothers, along with 52 unrelated normal controls. Overall, 76% of the affected children, 75% of the unaffected siblings, 69% of fathers and 59% of mothers were positive for either blocking or binding Ab, whereas the prevalence of this Ab in the normal controls was 29%. The Ab was highly prevalent in affected families including unaffected siblings. The appearance of these antibodies may have a familial origin but the risk of developing ASD is likely influenced by other mitigating factors since some siblings who had the antibodies were not affected. The antibody response appears heritable with the blocking autoantibody in the parents and affected child increasing the risk of ASD. Autism Res 2018, 11: 707-712. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Folate is an essential nutrient during fetal and infant development. Autoantibodies against the folate receptor alpha can block folate transport from the mother to the fetus and to the brain in infants. Children diagnosed with autism and their immediate family members were evaluated for the prevalence of folate receptor autoantibodies. The autoantibody was highly prevalent in affected families with similar distribution in parents, normal siblings and affected children. The presence of these antibodies appears to have a familial origin and may contribute to developmental deficits when combined with other factors.
Autism research : official journal of the International Society for Autism Research, 2018 · doi:10.1002/aur.1934