Fluorescence-activated cell sorting of mouse-human hybrid cells aids in locating the gene for the Leu 7 (HNK-1) antigen to human chromosome 11.

Leu 7 (HNK-1) is a membrane antigen expressed on human natural killer cells and some other lymphoid cells. Starting with two clones of mouse-human hybrid lymphoid cells that had 1.6% and 35% Leu 7-positive cells, respectively, we viably sorted Leu 7-positive and -negative cells using a fluorescence-activated cell sorter (FACS). Short-term progeny of the sorted cells were then karyotyped. Chromosome 11 was the only human chromosome that was absent from the Leu 7-negative population and present in nearly all of the progeny of the Leu 7-positive selected cells. Thus, we assigned the Leu 7 gene to chromosome 11.