Amplification and loss of repeat units of the human minisatellite MS1 integrated in chromosome III of a haploid yeast strain.

Minisatellites comprise arrays of tandemly repeated short DNA sequences which show extensive variation in repeat unit number. The mechanisms that underlie this length variation are not understood. In order to study processes influencing length changes of minisatellites, we integrated the human minisatellite MS1 into a haploid strain of the yeast Saccharomyces cerevisiae. Frequent spontaneous generation of MS1 alleles with new lengths were observed in this yeast strain. Hence it is concluded that recombination between members of a pair of homologous chromosomes is not a prerequisite for the generation of length changes in MS1 in yeast.