The rare blood group phenotype lacking Lutheran antigens, Lu(a-b-), is known to have two genetic backgrounds. Tests on 250000 blood donors show the frequency of Lu(a-b-) to be approximately 1 in 3000. The families of 41 propositi show the dominant inhibitor of Lutheran antigens, In(Lu), to be the usual cause of the phenotype in South East England; there was no proven case of the recessive background, LuLu. Lod scores for In(Lu) and other blood group loci are presented; the only hint of linkage is between In(Lu) and Rh. The suppressing effect of In(Lu) on the expression of antigens of unrelated blood group systems, P1, Aua and i, is confirmed.
Antibodies to various high-frequency antigens were used to test red cells of members of 12 families of Lu(a-b-) propositi carrying the In(Lu) gene. Kna, Kna-like, McCa, and Sla usually are expressed more weakly on cells of the Lu(a-b-) members than on those of their relatives who were not Lu(a-b-). In most families, In(Lu) also suppresses Yka and Csa expression. Some antiserums are more efficient than others of the same specificity in demonstrating the weakened expression. The expression of Ch and Rg antigens on red cells is not affected by In(Lu).
Anti-Sc1 was detected in a gravida-2 patient at 12 weeks' gestation. At 29 weeks, the antibody was found to be of the IgG3 subclass with a titer of 16, score 36, by the indirect antiglobulin test, and it produced 7 percent lysis by antibody-dependent cellular cytotoxicity (ADCC) assay, a finding that suggested an unaffected fetus. The titer remained constant throughout the pregnancy, as did the IgG subclass and activity in the ADCC assay. At delivery of the full-term infant, the cord hemoglobin was 13.5 g per dL and the direct antiglobulin test was positive (3+) with anti-IgG. The infant did not require transfusion. A sample taken 9 weeks after delivery showed 44 percent lysis in the ADCC assay. The anti-Sc1 titer was 32, score 65.
BOW is a 'new' low-frequency red-cell antigen, detected in 2 unrelated English blood donors, that is sensitive to alpha-chymotrypsin and pronase. Anti-BOW is present in many polyspecific reagents used to define low-frequency antigens. Red-cell groups of the proposita, R.B., and her family show that the BOW blood group segregates independently from the ABO, Rh, MNSs, P1 and Kell blood group systems.
The Skjelbred (Sk) antigen has been studied in the donor population of South London and found to have a frequency of 0.0035%. Its presence in serum as well as on red cells, its transient nature and its absence in relatives of Sk(+) individuals are suggestive of a non-genetic background for Sk. The antibody is not uncommon in normal donor sera (3--12%).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.