A Low‐Incidence Red Cell Antigen JAL Associated with Two Unusual Rh Gene Complexes

Abstract

A multilaboratory investigation during several years has identified a low incidence antigen JAL on the red cells of 7 propositi. JAL appears to be associated with two unusual Rh complexes, one of which produces a depressed C antigen and the other a depressed c antigen. Family studies strongly suggest that the JAL antigen is encoded by the RH locus. Anti-JAL has been implicated in haemolytic disease of the newborn and is thus considered to be a clinically significant antibody.

The Red Cell Antigen JAL in the Swiss Population: Family Studies Showing That JAL Is an Rh Antigen (RH48)

“…Rh32 [6] and Rh35 [7] have been found, in all instances, to be associated with weak expression of C and e whilst Rh36 (Bea) [8, p. 204] is associated with weak expression of c and e. In contrast, the antigens C" and Cx are usually associated with C+ complex es but may, on occasion, also be found with C-complexes [8, p. 215, 9,10]. To date, JAL appears to be encoded by a Ce complex in Whites and a ce complex in Blacks; it is fortuitous that both types were recognised during the same study [1]. In the five Swiss families studied, the JAL antigen is a…”

“…marker of a CDe antigenic complex with weaker than nor mal expression of C and e antigens. Previously reported JAL+ individuals of White ancestry also had a CDe anti genic complex with depressed C and e antigens whilst the JAL+ phenotype of individuals of Black ancestry was asso ciated with weak expression of c and e antigens [1]. Lowincidence Rh antigens which are markers of gene complex es have been previously described.…”

“…Two other anti-JAL (S. Allen and J. McD. [1]) were used to confirm the JAL status of positively reacting samples. Anti-IgG was obtained from the BPL(D), Elstree.…”

“…The JAL antigen is a newly described low-incidence antigen associated with two unusual Rh gene complexes [1]. The JAL antigen in Whites is associated with weak expres sion of C antigen and in Blacks with weak expression of c antigen.…”

“…The JAL antigen in Whites is associated with weak expres sion of C antigen and in Blacks with weak expression of c antigen. Both gene complexes appeared to carry less than normal amounts of e antigen [1], Studies undertaken on families of five JAL+ propositi hinted at possible linkage between JAL and RH [1], An example of anti-JAL, J. Pas., was used to test blood donors in Switzerland; four new propositi were detected.…”