DNA profiling of B chromosomes from the yellow-necked mouse Apodemus flavicollis (Rodentia, Mammalia)

Using AP-PCR-based DNA profiling we examined some structural features of B chromosomes from yellow-necked mice Apodemus flavicollis. Mice harboring one,two, or three or lacking B chromosomes were examined. Chromosomal structure was scanned for variant bands by using a series of arbitrary primers and From these, informative bands were selected. The selection:criteria used were the ability to differentiate between individuals of the species, to detect markers common For both A and B chromosomes, and, importantly, to differentiate between A- and B-chromosome sets. In addition to primers, profiling conditions were found to be critical for meeting the selection criteria. Primers and analysis conditions that demonstrated structural characteristics unique to the B-chromosome set are described. These characteristics included variant bands as qualitative parameters and altered electrophoretic band-intensities as quantitative distinctions estimated by integration of densitometric profiles of electrophoretograms. B chromosome-specific molecular markers are easy to detect by AP-PCR-based DNA profiling in the presence of a full set of A chromosomes. Models for the origin of yellow-necked mouse B chromosomes are discussed in the context of presented data