Peroxidase (HRP) conjugates of Arachis hypogaea agglutinin (PNA), Dolichos biflorus (DBA), Ulex europaeus agglutinin I (UEA I) and Bandeiraea simplicifolia agglutinin I (BSA I) are used to detect the expression of carbohydrate moieties in glycoconjugates of normal human duodenal mucosa. Lectin histology is performed on sections from paraffin embedded specimens of donor blood groups A, B, AB and 0.