Abstract
Sialic acids are components of cell-surface glycans and play important roles in cell–cell communication and host–pathogen interaction. More than 55 genes, encoding receptors, enzymes, and transporters, are known to be involved in sialic acid biology. Nearly 10 years of research have revealed that several of these genes show human-specific changes in genome structure, expression, or function. In this chapter, we introduce these human-specific changes and their possible impact on the human evolution. Also, we give an overview of the evolution of sialic acid biology in primates. The discovery of human-specific changes in sialic acid biology is one step toward explaining the genetic basis of human uniqueness, one of the major activities in primatology, contributing to answering a transdisciplinary question: What makes us human?