The Essay “The future of humans as model organisms” (10 Aug, p. 552) highlighted the potential to incorporate more “real-world” testing into biomedical research. Here we propose that the biomedical research community also takes a closer look at other genetically outbred animals in more natural environments. This approach would satisfy key points highlighted by FitzGerald et al.: (i) broadening the diversity of populations studied, (ii) taking advantage of natural “gene knockouts”, (iii) quantifying “physiological noise” due to genetics and the environment (1).
For example, bats, rodents and wild birds harbor many pathogens (e.g. rabies, hantavirus, influenza), thus providing insights into how these hosts are protected, which may lead to parallel insights for other species. Further, transmissible tumors in dogs (2) and Tasmanian devils (3, 4) are simultaneously a cancer, infectious disease, and allograft and provide opportunities to investigate immune regulation and evasion. Advances in monitoring techniques (e.g. remote-sensing) for these natural experiments allow a “more direct linkage to functional outcomes” (10 Aug, p. 553), such as fecundity and survival. Furthermore, these real-world “experiments” might have improved translational capacity for humans and veterinary medicine and stimulate ideas that are unlikely to be conceived in laboratory-based studies.
Finally, several amphibian, bat, and ape populations are in decline largely due to diseases (chytridiomycosis (5, 6), white nose syndrome (7), and ebola virus (8, 9)), therefore, fundamental knowledge gained from studying these natural disease models may not only advance human medicine but could also impact wildlife conservation for many generations. The increasing availability of genomes and “omics” approaches for non-model species has opened many new research pathways. However, to realize the full conservation and biomedical research potential a coordinated effort by an international consortium to develop species-specific reagents is needed.
References and Notes:
1. G. FitzGerald et al., The future of humans as model organisms. Science. 361, 552–553 (2018).
2. C. Murgia, J. K. Pritchard, S. Y. Kim, A. Fassati, R. A. Weiss, Clonal Origin and Evolution of a Transmissible Cancer. Cell. 126, 477–487 (2006).
3. A.-M. Pearse, K. Swift, Allograft theory: transmission of devil facial-tumour disease. Nature. 439, 549 (2006).
4. R. J. Pye et al., A second transmissible cancer in Tasmanian devils. Proc. Natl. Acad. Sci. 113, 374–379 (2016).
5. J. Voyles et al., Shifts in disease dynamics in a tropical amphibian assemblage are not due to pathogen attenuation. Science. 359, 1517–1519 (2018).
6. J. Alan Pounds et al., Widespread amphibian extinctions from epidemic disease driven by global warming. Nature. 439, 161–167 (2006).
7. J. M. Lorch et al., Experimental infection of bats with Geomyces destructans causes white-nose syndrome. Nature. 480, 376–378 (2011).
8. P. D. Walsh et al., Catastrophic ape decline in western equatorial Africa. Nature. 422, 611–614 (2003).
9. K. L. Warfield et al., Vaccinating captive chimpanzees to save wild chimpanzees. Proc. Natl. Acad. Sci. 111, 8873–8876 (2014).