Immunogenetic Studies of Cellular Antigens: Individual Differences between Species Hybrids.

REVIOUS papers from this laboratory have dealt with segregation of antiP genic characters of the red blood cells, peculiar to one or the other of the parental species, in hybrids from matings between Pearlneck (S t rep tope lk chinensis) and Ring dove (St. risoria) , Pearlneck and Senegal (St. senegalensis), and others. The use of the immunological technics described in these papers gave results which allow the conclusion that, in a comparison of these pairs of species, each possesses two kinds of cellular antigens-namely, (a) those antigens which are common to both species and (b) those which are specific to each. Indeed, similar comparisons between several species of the genus Columba have given results which make it plausible to state that parallel conclusions may be made in the comparison of any two species, whether or not they may hybridize. References to the pertinent papers have been given in a recent review (IRWIN and CUMLEY 1943). Many if not all of the cellular antigens which differentiate Pearlneck from Ring dove have been obtained in unit form (IRWIN 1939). Furthermore, both genetic and immunological tests coincide in showing that, of the nine or ten cellular characters specific to Pearlneck (d-I, d-2, d-3, d-4, d-5, d-6, d-7, d-4 d-8, d-9 and d-II), Senegal shares with Pearlneck all of d-I, d-2, d-3, d-4, d-5, d-4.d-8, d-9, but only a part of d-6, d-11 and of one or more others (IRWIN and COLE 1940). That is, several characters specific to Pearlneck, in comparison with Ring dove, are also specific to Senegal and represent antigens shared by the two species to the mutual exclusion of Ring dove. Hybrids have now been obtained between Senegal and Ring dove, and backcross offspring are being produced in matings to the latter. The cells of the species hybrids have been tested for differentiation of the individuals and in relation to the specific characters of Pearlneck. The antigenic differences between these species hybrids are considered in this paper. In comparison, individual differences in antigens peculiar to Pearlneck among the hybrids from the cross of Pearlneck and Ring dove have been rarely found (IRWIN and COLE 1936; and unpublished data on other hybrids of this cross).