Experiment
Genome scan was performed on phenotypically extreme animals from a (C57BL/6J x DBA/2J)F2 population to identify QTLs associated with predicted percent body fat and fat pad percentage. Eighty evenly spaced microsatellite markers were screened. Several obesity candidate genes were also analyzed (agouti chr2, 92 cM; Lepr chr4, 47.5 cM; Lep chr6, 10.4 cM; Tub chr7, 49.5 cM; Cpe chr8, 15.9 cM).
Loci showing significant linkage to predicted fat percentage mapped to mouse Chromosomes 4 (Pfat1), 6 (Pfat2), 13 (Pfat3), and 15 (Pfat4). Pfat1 mapped to 30 cM on mouse Chromosome 4 with LOD=5 at D4Mit81. Pfat2 mapped to 38.1 cM on mouse Chromosome 6 with LOD=4.9 at D6Mit102. Pfat3 mapped to 20 cM on mouse Chromosome 13 with LOD=5.3 at D13Mit248. Pfat4 mapped to 43.3 cM on mouse Chromosome 15 with LOD=8.6 at D15Mit29.
A locus on mouse Chromosome 5 showed suggestive linkage to fatness at D5Mit227 (4 cM, LOD=3.1). The candidate genes did not show significant linkage to fatness. No linkage to fat pad percentage was detected.