CONSTRUCTION OF CHICKEN X HUMAN MICROCELL HYBRIDS FOR HUMAN GENE TARGETING

Human chromosomes 1, 2, 3, and 11 were tagged with pSV2 neo and transf erred via microcell fusion from mouse A9 human monochromosomal hybrids to a chicken pre-B cell line, DT40, proficient for homologous recombi nation. Hybrids containing two copies of human chromosome 11 were tran sfected with targeting vectors containing a mammalian selectable gene with either the D11S16 or HRAS genomic sequences corresponding to two different chromosome 11 loci. Analysis of stable transfectants showed a high frequency (similar to 80%) of targeted integration of these con structs into each of the homologous loci of human chromosome 11 in DT4 0 hybrids. The results suggest that any human genomic sequences on hum an chromosomes transferred into DT40 cells could be targeted at high f requency, thereby allowing for subsequent modification of human genes and chromosomes.