Hyperserotoninemia and antiserotonin antibodies in autism and other disorders.
Serotonin-targeting antibodies do not single out autism, so stick to behavioral diagnosis.
01Research in Context
What this study did
Yuwiler et al. (1992) drew blood from people with autism, schizophrenia, OCD, Tourette's, and mixed diagnoses. They looked for two things: high serotonin and antibodies that attack serotonin. The goal was to see if either marker was autism-specific.
What they found
The lab found no clear link. High serotonin showed up in several groups, not just autism. The serotonin-blocking antibodies also appeared across diagnoses. Neither test pointed only to autism.
How this fits with other research
Schneider et al. (2006) and Lecavalier et al. (2006) later reviews still list high blood serotonin as the best-supported chemical clue in autism, but they fold the 1992 antibody failure into their "mixed evidence" pile.
Andrews et al. (2024) moves the field forward. That team used an eight-autoantibody panel and reached 94 % accuracy for spotting ASD severity. Their blood test supersedes the 1992 single-antibody approach.
Oblak et al. (2013) extends the hunt from blood to brain. Post-mortem tissue showed fewer serotonin receptors in social-emotional areas of autism brains. This shifts focus from antibodies in plasma to receptors in cortex.
Why it matters
As a BCBA you can stop worrying about serotonin antibody tests. They are not a diagnostic tool. Keep using behavioral assessments. If a family mentions new immune-based blood panels, point them to newer data like Andrews et al. (2024) and away from the old single-antibody idea. Your session time is better spent on skill acquisition and behavior reduction, not chasing inconclusive biomarkers.
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02At a glance
03Original abstract
This study examined the linkage between elevated blood serotonin in autism and the presence of circulating autoantibodies against the serotonin 5HT1A receptor. Information was also obtained on the diagnostic and receptor specificity of these autoantibodies. Blood serotonin was measured as was inhibition of serotonin binding to human cortical membranes by antibody-rich fractions of blood from controls and from patients with childhood autism, schizophrenia, obsessive-compulsive disorder, Tourette's, and multiple sclerosis. The results showed elevated blood serotonin was not closely related to inhibition of serotonin binding by antibody-rich blood fractions. Inhibition of binding was highest for patients with multiple sclerosis and was not specific to the 5HT1A receptor as currently defined. Although inhibition was not specific to autism, the data were insufficient to establish if people with autism differed from normal controls on this measure.
Journal of autism and developmental disorders, 1992 · doi:10.1007/BF01046401