Using Evolutionary Biology in the Medical Sciences
Published Online: 15 JAN 2010
Copyright © 2001 John Wiley & Sons, Ltd. All rights reserved.
How to Cite
Antolin, M. F. 2010. Using Evolutionary Biology in the Medical Sciences. eLS. .
- Published Online: 15 JAN 2010
Applying evolutionary thinking to medical practice can lead to unraveling ultimate causes of disease and in improving diagnostics and therapies. Genetic variation is central: adaptations evolve by natural selection of inherited differences linked to survival and reproduction. Thus we may ask why diseases persist. Genetic diseases recur because long-term population size and histories of selection influence the number of disease-causing mutations patients carry. Individuals present different symptoms because mutations interact with environmental and genetic backgrounds. Some diseases like diabetes and hypertension persist because of mismatches between previous adaptation and modern environments. For infectious diseases, rapid evolution in microbes underlies the drug resistance blocking improvement of public health and prevents design of vaccines with long-lasting protection against human-adapted pathogens like influenza and malaria. A key is that diseases represent convergence of several evolutionary histories: the patient's legacy of inherited mutations and adaptations, and the microbes' history of infection, pathogenicity and transmission.
Evolutionary thinking in medicine distinguishes between proximate and ultimate evolutionary causes of disease.
Mutations that cause disease in modern times may have been adaptive in the past, and thus produce traits that are maladaptive (mismatched) in modern environments.
Early developmental problems may lead to disease in adults because of trade-offs in early versus late life history traits.
Weak selection on diseases related to ageing explains their persistence in modern times especially as post-reproductive longevity increases.
The evolutionary potential of microbes ensures that infectious diseases will evade therapies and vaccines in the future.
Disease symptoms may represent adaptations to slow pathogen reproduction, so treating symptoms may prolong the course of infections and opportunities for pathogen transmission.
The evolutionary potential of microbes makes it likely that new diseases will continue to emerge from reservoirs in wild animal populations.
Medical research on therapies and diagnostics depends on testing animals most closely related and thus most similar to humans.
Individual patients’ presentation of disease will depend on complex interactions at the convergence of patients’ genetic legacies, the evolutionary history of pathogens to which they are exposed, and the environmental context where the patients and pathogens meet.
- environmental mismatch;
- fitness trade-off;
- genetic disease;
- infectious disease;
- natural selection;
- pathogen evolution