Further evidence of X-linkage of hypoxanthine phosphoribosyl-transferase in the mouse.

A variant of the HPRT-A9 mouse cell line was fused with wild type diploid mouse bone marrow cells to obtain an HPRT+ line. The unique chromosomal features of the A9 parent, including the presence of a t(X;3) translocation and the absence of normal chromosomes 15,16, 17, 18, and the X, have permitted use of this intraspecific hybrid for chromosome mapping. Back-selection of hybrid cells in 8-azaguanine for loss of HPRT resulted in the loss of the Xchromosome derived from the diploid parent, providing evidence of the X-linkage of the HPRT locus.