A Meta-analysis of QTL Associated with Body Weight and Adiposity in Mice

Objective: Cross-breeding experiments with different mouse strains have successfully been used by many groups to identify genetic loci that predispose for obesity. In order to provide an assessment of these QTL as a basis for a systematic investigation of candidate genes, we have performed a meta-analysis of genome-wide linkage scans for body weight and body fat. Data: From a total of 34 published mouse cross-breeding experiments, we compiled a list of 113 non-redundant QTL for body weight and 89 QTL for fat weight and body fat percentage. Collectively, these studies include data from 42 different parental mouse strains and >14 500 individual mice. Methods: The results of the studies were analysed using the truncated product method (TPM). Results: The analysis revealed significant evidence (LOD score >3.0) for linkage of body weight and adiposity to 30 different segments on ten chromosomes. The most prominent regions with linkage for body weight and body fat (LOD scores 6.7–17.8) on chromosomes 1, 2, 7, 11, 15, and 17 contain a total of 54 QTL for body weight and body fat. At least 34 candidate genes and genetic loci which have been implicated in regulation of body weight and body composition in rodents and/or humans are found in these regions, including CCAAT/enhancer binding protein alpha (C/EBPA), sterol regulatory element binding transcription factor 1 (SREBP-1), peroxisome proliferator activator receptor delta (PPARD), and hydroxysteroid 11-beta dehydrogenase 1 (HSD11B1). Our results demonstrate the presence of numerous distinct consensus QTL regions with highly significant LOD scores that control body weight and body composition.