The analysis of genomic DNA methylation profiles revealed hundreds of genes hypo- and hypermethylated in the heart, spleen, and liver of the MRL/MpJ mouse strain in comparison with the C57BL/6J control, and 37 of these genes were differentially methylated in the three examined tissues.
Individually they represent classifiers, but taken together they represent a group of genes whose expression has been altered in the different mouse strains in comparison to the wild-type.
A combination of three methods of array pre-processing was used to compile a list of ranked transcripts covered by 1528 probe-sets significantly different between the mouse strains under comparison.
Currently, the Mouse Phenome Database (MPD), which includes dbSNP and Perlegen data among other resources, offers the most inclusive SNP queries for mouse strains, including comparisons of the D2 and B6 strains (see Methods for further explanation of SNP Databases).
To compare drug effects within each mouse strain, we performed pairwise comparisons, comparing drugs and comparing drug-incubation pairs.
We chose to perform the methacholine provocation with the same methacholine concentrations for each mouse strain to make comparisons easier.
Our results may serve as reference dataset for normal body weight and composition in the C57BL/6J mouse strain and assist in the comparison of wild-type animals with models of growth or altered body composition for future studies.
With the advent of next-generation, high-throughput sequencing (HTS), we are now in a position to determine to what extent polymorphisms remain cryptic (either undiscovered or not previously annotated as a SNP in a specific strain comparison) in various mouse models and assess their impact on downstream analyses.
Using the same test setup, the initially highly anxious DBA mouse strain revealed a different exploratory strategy in comparison with the low-anxiety C57BL/6 strain, resulting in fewer memory errors over time (Ohl, Roedel, Binder, & Holsboer, 2003).
Post hoc pairwise significance tests comparing specific mouse strain pairs were performed using Tukey's honestly significant difference test to control for multiple comparisons.
Strain comparison indicated that the BALB/c mice had significantly higher airway reactivity than C57BL/6 mice (P<0.001).
