Schematic of subcongenic and subsubcongenic strains derived from strain 6C2 and 6C2d. (A) The location of Obrq2 is indicated relative to chromosome 6. Map of chromosome 6 subcongenic (B) and subsubcongenic (C) panels that define QTLs for body weight and measures of insulin resistance. Obrq2 is located in a 30.3-Mb interval between markers rs13478633 and rs30218447 that differs genetically between the 6C1 obesity-susceptible and 6C2 obesity-resistant congenic strains (see also panel B) (Buchner et al. 2010). Strain names are indicated on the left. Body weight data are presented as mean ± SEM. An asterisk indicates statistical significance (P < 0.05) following adjustment for Bonferroni correction. QTL intervals are arbitrarily drawn with the proximal and distal boundaries halfway between the flanking markers. (BW) QTL regulates body weight; (Gluc) QTL regulates fasting glucose levels; (Ins) QTL regulates fasting insulin levels. The overlap between Obrq2d with both Obrq2a and Obrq2c as well as Obrq2a6 with both Obrq2a3 and Obrq2a4 may indicate a common genetic basis for the overlapping QTLs rather than distinct QTLs.
