MULTILOCUS FINGERPRINT BANDS ARE ASSOCIAT ED WITH THE GROWTH-PERFORMANCE IN SELECTED MOUSE LINES - LINKAGE ANALYSIS IN REFERENCE FAMILIES

In this study long term body weight-selected lines of mice were charac terised using multilocus DNA fingerprinting with the simple tandem rep etitive oligonucleotide probes (GAA)(6) and (GACA)(4). Based on DNA fi ngerprint analysis in corresponding reference families polymorphic fin gerprint bands were identified which are associated with the growth pe rformance. Mixed DNA samples of ten unrelated individuals of trait-sel ected mouse lines (for over 60 generations) and the unselected control lines were analysed. The resulting differences in banding patterns we re reanalysed by comparing individual fingerprints of the animals incl uded in the mixed DNA samples of the different lines. Comparing the mo use lines about 30 % of analysed fingerprint bands were polymorphic. I ndividuals of long term selected mouse lines show only few individual- specific bands. In the DNA mixes most polymorphic bands differing betw een the lines appear in all individual animals of the corresponding li ne. Line-specific DNA fingerprint bands were analysed for their inheri tance and linkage with growth performance in reference families using animals with extreme ''growth performance'' of the first backcross-gen eration after crossing of weight selected with unselected mice. By fol lowing the inheritance of line-specific bands in the reference panel t hree bands are associated with ''growth performance''. Nevertheless mo st line-specific bands result from genetic drift rather than from sele ction.