Ajit Varki is a Distinguished Professor of Medicine and Cellular & Molecular Medicine and co-director of the Glycobiology Research and Training Center at UC San Diego School of Medicine.
Varki’s lab studies a family of sugar molecules called the sialic acids, which are found at the outermost position on the glycan chains of all vertebrate cell surfaces and glycoproteins, and their roles in biology, evolution, and disease. These glycans are known to mediate or modulate many biological processes including sub-cellular and cellular trafficking, intercellular adhesion, signaling, and microbial attachment. Much data also indicates their involvement in embryonic development, normal tissue organization, tumor metastasis, and in the interactions of cells with extracellular molecules. His lab is focused on understanding the differences in sialic acid biology between humans and several ape species, including chimpanzees.
In a proof-of-concept study published in the journal PNAS in 2017, Varki and his team discovered a new kind of glycan that survives even in a 4 million-year-old animal fossil from Kenya, under conditions where ancient DNA did not. “In recent decades, many new hominin fossils were discovered and considered to be the ancestors of humans,” said Varki in a release on the study. “But it’s not possible that all gave rise to modern humans — it’s more likely that there were many human-like species over time, only one from which we descended. This new type of glycan we found may give us a better way to investigate which lineage is ours, as well as answer many other questions about our evolution, and our propensity to consume red meat.”
Varki is an elected member of the American Academy of Arts and Sciences, the Institute of Medicine, the American Society for Clinical Investigation, and the Association of American Physicians.
Varki has received numerous honors, among them, the Karl Meyer Award of the Society for Glycobiology (2005) and the International Glycoconjugate Organization Award (2007). He is also co-director of the Center for Academic Research and Training in Anthropogeny and he was appointed as an adjunct professor at the Salk Institute for Biological Studies.