TANDEMLY REPEATED TRANSGENES OF THE HUMAN MINISATELLITE-MS32-(D1S8), WITH NOVEL MOUSE-GAMMA SATELLITE

The human hypervariable minisatellite MS32 has a well characterised in ternal repeat unit array and high mutation rates have been observed at this locus. Analysis of MS32 mutants has shown that male germline mut ations are polarised to one end of the array and frequently involve co mplex gene conversion-like events, suggesting that tandem repeat insta bility may be modulated by cis-acting sequences flanking the locus. In order to investigate the processes affecting MS32 mutation rate and m echanism, we have created transgenic mice harbouring an MS32 allele. H ere we describe the organisation of eight transgenic insertions. Analy sis of these transgenic loci by MVR-PCR and structural analysis of the junctions between mouse flanking DNA and the transgenic loci has shed light on mechanisms of integration and rearrangement of the tandem re peated transgenes. Sequence analysis of the moose DNA flanking these t ransgenes has shown that 5 of the 8 insertions have integrated into mo use gamma satellite repeated sequence. This suggets a non-random integ ration of the MS32 transgene construct into the mouse genome.