Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden.
Level 3 - non-randomized controlled study
Observational cohort/cross-sectional study of gene-pathogen interactions and cognition
PubMed 28031319 · doi:10.1096/fj.201601084R
What was done
Researchers assessed the interactions between apolipoprotein E4 (E4) allele carrier status, parasite burden, and cognitive performance in a cohort of 372 Amazonian forager-horticulturalists living in a traditional, nonindustrialized environment.
What was found
The abstract reports no numerical values, effect sizes, or test statistics. Directionally, older adult E4 carriers with high parasite burdens maintained or showed slight improvements in cognitive performance, whereas non-E4 carriers with a high parasite burden showed reduced cognitive performance.
Why it matters
While ApoE4 is the strongest known genetic risk factor for Alzheimer's disease in industrialized settings, these findings suggest it may confer cognitive protection or evolutionary advantages in pathogen-rich environments.
Limits
The abstract reports no numerical data, confidence intervals, or specific cognitive and parasite burden metrics. The sample is limited to a single nonindustrialized population (N = 372), and the observational design precludes causal inferences.
Cited by
- supports A study in an indigenous Bolivian tribe found that the APOE-e4 allele was protective against cognitive decline in individuals with high parasite burdens.
- supports Approximately 20% of human populations carry the APOE-e4 allele.