Synergic effect of GSTP1 and blood manganese concentrations in Autism Spectrum Disorder.
Among young Jamaican children, carrying the GSTP1 Ile/Ile gene plus blood manganese ≥12 µg/L sharply raises autism odds.
01Research in Context
What this study did
Researchers looked at Jamaican kids aged 2-8 with and without autism.
They checked blood manganese levels and a gene called GSTP1.
The goal was to see if high manganese plus certain genes raised autism odds.
What they found
Kids who had the GSTP1 Ile/Ile gene and manganese at or above 12 µg/L faced 4-6 times higher odds of ASD.
The link only showed up in this one gene-metal pair.
How this fits with other research
Zwiya et al. (2023) used the same Jamaican group and added girls, lead, and mercury.
Sex changed the results: the GSTP1-metal link held for boys but was shaky for girls.
Mulder et al. (2020) also tested Jamaican kids, yet found lower PCB pesticide levels tied to ASD.
Both papers point to gene-toxin links, but the direction flips—high manganese raises risk while low PCBs seem to.
The difference likely comes from distinct toxins and genes (GSTP1 vs GSTM1).
Why it matters
When you take an environmental history, ask about well water, old pipes, or steel work that can boost manganese.
If the family mentions these sources and the child has the Ile/Ile GSTP1 result, flag the combo for closer developmental tracking.
You cannot change genes, but you can suggest water testing or diet tweaks to lower future exposure.
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02At a glance
03Original abstract
We used data from 100 age- and sex-matched case-control pairs (age 2-8 years) from Jamaica to investigate whether there is an interaction between glutathione-S-transferase (GST) genes and blood manganese concentrations (BMC) in relation to Autism Spectrum Disorder (ASD). Our findings, indicate that among children who had the Ile/Ile genotype for GST pi 1 (GSTP1), those with BMC ≥ 12µg/L had about 4 times higher odds of ASD than those with BMC < 12µg/L, (P=0.03) under a co-dominant genetic model. After adjusting for potential confounders, among the subgroup of children with genotype Ile/Ile, those with BMC ≥ 12µg/L had about six times higher odds of ASD than those with BMC < 12µg/L, (P=0.04). The results were similar when a recessive genetic model was used. These findings suggest a possible synergic effect of BMC and GSTP1 in ASD. Since our analysis included a variety of genetic models and was not adjusted for multiple testing, replication in other populations is warranted.
Research in autism spectrum disorders, 2015 · doi:10.1016/j.rasd.2015.08.001