INFLUENCE OF BLOOD-GROUP AND SECRETOR STATUS ON CARBOHYDRATE STRUCTURES IN HUMAN GASTRIC MUCINS - IMPLICATIONS FOR PEPTIC-ULCER

1. The content and distribution of carbohydrate was examined in mucus glycopolypeptides from human antral mucosae, 2,The mean amount of carb ohydrate per 1000 amino acid residues was found to be similar in glyco polypeptides with A, B or H activity, It was slightly, though signific antly, less in glycopolypeptides lacking these determinants, because c arbohydrate chains were of a shorter average length than in the A-, B- or II-active preparations, This difference was reflected in the sizes of oligosaccharide-alcohols released from representative glycopolypep tides with alkaline borohydride. 3, Differences between A-, B- or II-a ctive and non-secretor glycopolypeptides in terms of the mean number o f carbohydrate chains per 1000 amino acid residues were found to be sm all, and without significance, 4, The average number of peripheral mon osaccharide units per 1000 amino acid residues was greater in A-active than in H-active, and least in non-secretor, glycopolypeptides, This order was reversed for monosaccharide units incorporated into skeletal (core plus backbone) structures, The difference in each case was stat istically significant, 5, These findings suggest that the increased ri sk of peptic ulcer associated with blood group O and non-secretor stat us is unlikely to be attributable to an inherent deficiency in the pro tective mucus layer, linked to differences between mucins that are ass ociated with A, B or H activity, Other hypotheses linked to infection with Helicobacter pylori are examined.