Human Genetic Disorders and Knockout Mice Deficient in Glycosaminoglycan
Figure 1
Typical repeating disaccharide units in CS, DS, HS, and heparin, and their potential sulfation sites. CS consists of GlcUA and GalNAc, whereas DS is a stereoisomer of CS including IdoUA instead of GlcUA. Both linear polysaccharides are often found as CS-DS hybrid chains in mammals. HS and heparin consist of uronic acid and GlcNAc residues with varying proportions of IdoUA. Heparin is highly sulfated and has a large proportion of IdoUA residues, whereas HS is low sulfated and has a high proportion of GlcUA. These sugar moieties are esterified by sulfate at various positions as indicated by the circled “S.” The abbreviation of “i” in iO, iA, iB, iC, iD, and iE stands for IdoUA. HexUA represents hexuronic acid (GlcUA or IdoUA).
