THE PREVALENCE OF SECRETOR STATUS AND CO-EXPRESSION OF LEWIS ANTIGEN IN VOLUNTARY BLOOD DONORS

: Blood group substances are present in soluble form in a majority of individuals in secretion such as saliva and body fluids. Secretor status refers to the presence (SeSe and Sese) or absence (sese) of secretor gene which secrete ABH soluble substances. People having the secretor gene are called Secretors and those who do not have are called non-secretors. The ability to secrete ABH antigens is genetically inherited, approximately 80 percent are secretors and 20 percent are non-secretors. This percentage of secretor and non- secretor varies according to the race and ethnicity. The Lewis (Le) gene resides on Chromosome 19 and is distantly linked to H and Se loci. Lewis antigens are not intrinsic to the RBC but are synthesized in intestinal epithelial cells. This study was conducted in order to find out the prevalence of secretor status and co-expression of Lewis antigens in the voluntary blood donors. The method used to determine the secretor status was hemagglutination inhibition method. 5 ml of saliva was collected from a total number of 60 donors who participated in this study. 45 of them were found to be secretors and 15 of them were non-secretors .Their blood was used to detect the type of Lewis (Le) antigen since the type of Lewis antigen correlated with the secretor status of the individual, in which 39 out of 45 secretors were found to be Lewis b positive, 12 out of 15 non-secretors were found to be Lewis a positive. The remaining 6 secretors and 3 non-secretors were Lewis 'a' and 'b' negative. Keyword :Secretors, Non-secretors, Lewis antigen, Hemagglutination inhibition