Colton blood groups: indication of linkage with the Kidd (Jk) system as support for assignment to chromosome 7.

A material of normal Danish families was tested for a number of genetic marker systems and analyzed for linkage. For the Colton-Kidd relationship the lod score was + 2.57. The Kidd system has earlier been tentatively assigned to chromosome 7 (Schokeir et al. 1973). The present data therefore permit a tentative assignment to chromosome 7 of the Colton system as well. The data also suggest that the discovery by Chapelle et al. (1975) of a conjunction of monosomy for chromosome 7 in the bone marrow of certain leukemia patients and absence of Colton antigen from the red cells may now be interpreted as being connected with location on chromosome 7 of the Colton system.