Sexual Dimorphism in Telomere Length in Childhood Autism.
Telomere length flags biological stress only in autistic boys, not girls.
01Research in Context
What this study did
Panahi et al. (2023) measured telomere length in kids with autism.
They compared boys with autism to boys without autism and to sisters.
The team also compared girls with autism to girls without autism.
What they found
Autistic boys had shorter telomeres than both control boys and their own sisters.
Autistic girls looked the same as control girls.
Yet within autism, girls still had longer telomeres than boys.
How this fits with other research
Cohrs et al. (2017) saw the same boy-only pattern with blood serotonin.
Pre-pubertal boys with autism had high serotonin; girls did not.
Together the two studies say boys with autism carry a heavier biological load.
Agiovlasitis et al. (2025) add a behavioral angle.
Autistic boys played with toys typical for girls; autistic girls played like other girls.
The biomarker and play data line up: autistic boys differ from typical boys on both body and behavior.
Why it matters
If you assess a boy newly diagnosed with autism, know his cells may already show extra stress.
You can explain to parents that shorter telomeres do not change therapy today, but they remind us to watch health across the lifespan.
For girls, the lack of telomere change says their biology may travel a different road to autism.
Keep sex on your data sheet; it shapes both biology and behavior.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add a sex checkbox to your intake form and note any health red flags sooner for boys.
02At a glance
03Original abstract
Autism spectrum disorders (ASD) are strikingly more prevalent in males, but the molecular mechanisms responsible for ASD sex-differential risk are poorly understood. Abnormally shorter telomeres have been associated with autism. Examination of relative telomere lengths (RTL) among non-syndromic male (N = 14) and female (N = 10) children with autism revealed that only autistic male children had significantly shorter RTL than typically-developing controls (N = 24) and paired siblings (N = 10). While average RTL of autistic girls did not differ significantly from controls, it was substantially longer than autistic boys. Our findings indicate a sexually-dimorphic pattern of RTL in childhood autism and could have important implications for RTL as a potential biomarker and the role/s of telomeres in the molecular mechanisms responsible for ASD sex-biased prevalence and etiology.
Journal of autism and developmental disorders, 2023 · doi:10.1038/nrg3743