Fig. 2
From: Reporting phenotypes in mouse models when considering body size as a potential confounder
Example line Dlg4, where body weight confounds the phenotype. Body composition data were collected with a dual-energy X-ray absorptiometry at 14 weeks of age for the Dlg4 tm1e (EUCOMM) Wtsi/Dlg4 tm1e (EUCOMM) Wtsi knockout line on the C57BL6/N genetic background. The comparison was based on 249 female and 227 male wildtype mice and 7 female and 7 male knockout mice. a A scatterplot of the lean mass readings for the control and knockout animals for the males. b A scatterplot of the lean mass readings for the control and knockout animals for the females. c The genotype estimate with associated standard error and statistical significance when estimated using standard methodology (A1: Analysis Pipeline 1) and then after inclusion of body weight as a covariate (A2: Analysis Pipeline 2). As there was evidence of sexual dimorphism in the phenotype in A1, the genotype effect was estimated for male and female knockout mice separately. The scatter plots and analysis highlight how a body weight phenotype is observed in both sexes of the knockout animals and as the lean mass is associated with body weight, a statistically significant difference is seen in the lean mass until assessed as a relative abnormality