Chromosome fragmentation by chromosome mediated gene transfer.

Chromosome mediated gene transfer (CMGT) can be used to construct human-mouse somatic cell hybrids containing fragments of human chromosomes. We have constructed two panels of hybrid cells by CMGT: the first panel contains fragments of the human X chromosome and the second panel contains fragments of the Y chromosome. The construction of the Y chromosome panel was facilitated by the cotransfer of chromosomes with a selectable plasmid; selection for the plasmid encoded marker enriched for cells which had incorporated chromosome fragments. This preselection was combined with antibody dependent enrichment using the monoclonal antibody 12E7, which reacts with a Y-encoded antigen. Detailed investigation of the two panels revealed extensive rearrangements of the transferred fragments and the preferential retention of sequences from the centromeric region of the donor chromosomes. These results suggest that CMGT will not be particularly useful in the construction of genetic maps, but nevertheless CMGT can be used for enriching for specific regions of the human genome in somatic cell hybrids.