Maternal Serotonin Levels and Neurodevelopmental Severity in Autistic Children: A Partial Replication and Extension

Area of Science:

• Neuroscience
• Genetics
• Developmental Psychology

Background:

• The serotonin system is implicated in autism spectrum disorder (ASD).
• Previous research suggested lower maternal whole blood serotonin (WB5-HT) in mothers of children with severe autism.
• Replication of this finding in an independent cohort was investigated.

Purpose of the Study:

• To replicate the finding of lower maternal WB5-HT in mothers of children with severe autism.
• To investigate the relationship between maternal WB5-HT and autism severity.
• To explore associations between maternal WB5-HT and specific autistic traits.

Main Methods:

• Latent profile analysis was used to identify severity profiles in 259 children with autism.
• Maternal WB5-HT data from 162 participants were analyzed.
• Comparisons of maternal WB5-HT were made across severity profiles and quantiles.

Main Results:

• A three-profile solution (low, medium, high severity) was identified.
• Median maternal WB5-HT did not differ significantly across profiles.
• Maternal WB5-HT was lower at the 90th percentile of severity (adjusted p < .01) and negatively associated with social impairment.

Conclusions:

• This study did not replicate lower group levels of maternal WB5-HT in children with the highest autism severity.
• Children in the high-severity group were less likely to have WB5-HT in the upper range of the distribution.
• The absence of upper-range WB5-HT in this group warrants further investigation.