As we try to make sense of how a change in sodium channels in Neanderthals may have impacted pain sensitivity in modern humans, another recently illuminated cellular-level alteration in our ancestors sheds light on another aspect of our immunity: "How an ancient microbial arms race remodeled human cells" (Gibbons, Science. 31 Jul 2020, 369(6503): 491–492. doi: 10.1126/science.369.6503.491).
Our ancestors totally remodeled their cell surfaces in response to some past pathogen(s) over 2 million years ago. The dramatic make-over then required a major readjustment of the innate immune "machinery for sensing self." This readjustment mostly took place before Neanderthals and "anatomically-modern" humans diverged over .5 million years ago. Many human-specific pathogens have since adapted to recognize the human-specific cell surfaces to manipulate host immunity and to invade and infect.
Dive deeper into the details: "Multiple Genomic Events Altering Hominin SIGLEC Biology and Innate Immunity Predated the Common Ancestor of Humans and Archaic Hominins." (Khan et al. Genome Biol. Evol. 12(7):1040–1050. doi:10.1093/gbe/evaa125. Advance Access publication, 18 June 2020). OPEN ACCESS
TL;DR: "Are there human-specific diseases?" (Nissi Varki, 21 May 2020. "Impact of Infectious Disease on Humans and Our Origins," CARTA Symposium. OPEN ACCESS
Learn more about these UC San Diego scientists and the full spectrum of their research by exploring their CARTA Profiles below: