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Updated: May 25, 2026
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Published on: May 31, 2018
Host genetics and population structure effects on parasitic disease
Sarah Williams-Blangero1, Charles D Criscione, John L VandeBerg
1Department of Genetics, Texas Biomedical Research Institute, San Antonio, TX 78245, USA. sarah@txbiomedgenetics.org
Summary
Host genetics significantly impact infectious disease susceptibility. Within populations, host genetics are more crucial than population structure for Ascaris worm burden and Chagas disease progression.
Area of Science:
- Genetics
- Infectious Diseases
- Epidemiology
Background:
- Host genetic factors significantly influence susceptibility to infectious diseases.
- Population structure of hosts and parasites can affect disease distribution.
- Previous studies have identified host genetic determinants for parasitic diseases in specific populations.
Purpose of the Study:
- To assess the impact of population structure on infectious diseases.
- To compare the influence of within-population genetics versus population structure.
- To investigate these effects in Jirel (Nepal) and Brazilian populations.
Main Methods:
- Analysis of host genetic factors and population structure in two distinct populations.
- Assessment of Ascaris worm burden in the Jirel population.
- Evaluation of genetic influences on cardiac disease progression in Chagas disease patients in Brazil.
Main Results:
- Within-population host genetic effects were more significant than population structure for Ascaris worm burden.
- No significant influence of population structure was found on cardiac disease progression in Trypanosoma cruzi-infected individuals.
Conclusions:
- Host genetic factors play a more dominant role than population structure in shaping infectious disease patterns within these study groups.
- Population structure does not appear to be a major driver for Chagas disease cardiac progression in the studied Brazilian cohort.
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