SOUTH ASIAN AND EUROPEAN COLITICS SHOW CHARACTERISTIC DIFFERENCES IN COLONIC MUCUS GLYCOPROTEIN TYPE AND TURNOVER

South Asians in Britain have a high incidence of ulcerative colitis an d a low incidence of colorectal cancer. The pattern of mucus productio n in 12 South Asian and 16 European colitics and a control group of 19 South Asians was studied. Three types of mucin were identified after organ culture of colonic biopsy specimens with a dual label of [H-3]-g lucosamine and sodium [S-35]-sulphate: type A had a high [S-35]:[H-3] ratio and high incorporation ([H-3] dpm/mu g DNA >500); type B had a l ow ratio and high incorporation; and type C had low incorporation but with either high (C1) or low (C2) ratios. European colitic mucins show a significant reduction in the level of sulphation detected by mucin histochemistry with high iron diamine/Alcian blue staining, together w ith predominantly type B or C2 mucins (low sulphation). South Asian co litics showed histochemically normal patterns of high sulphation and l argely type A and C1 mucins (high sulphation). There was no correlatio n of mucin type with disease activity index in either ethnic group. Th e appearance of apparently normal mucin in patients with ulcerative co litis may be a useful marker for the patients. identification of a sub group at low risk of colorectal cancer.