PCA of the grouped CRH-R1 function abolition data. Biplot of gene scores and treatment group loadings according to the first two components of the PCA. The open circles or gene names represent the gene scores. The vectors represent the treatment group (variable) loadings. The biplot enables the association of genes with the treatment groups. Labeled genes were selected by permutation test.
Landgrebe et al. Genome Biology 2002 3:research0019.1 doi:10.1186/gb-2002-3-4-research0019