WES, a 'new' infrequent blood group antigen in Finns

A previously unrecognized infrequent blood group antigen WES occurs with a frequency of 0.56% in the Finnish population, but has an ethnically restricted distribution. Apart from Finns it was found only in 2 donors, most likely of African origin, among 4,655 people tested who represented many different ethnic groups. WES is shown to be a dominant autosomally inherited character different from previously published infrequent antigens. The data allow exclusion from almost all established blood group systems. The WES antigen is destroyed by enzymes alpha-chymotrypsin and pronase. It is also present in plasma of WES+ individuals. Evidence suggests that the soluble form of the antigen is a high molecular weight protein constituent of plasma. Unlike many other antigens present on red cells as well as in plasma, the WES antigen is well developed on red cells of neonates and can also be found in cord serum.