Figure 1

Determination of the average expression stability ( M ) of the reference genes using the geNorm program. The reference genes were serially excluded from the analysis, with M representing the mean pairwise variation between an individual reference gene and all other tested reference genes. The reference gene indicated at each point on the x-axis is the one that is to be excluded from the following step. The most stable reference genes are those that are still included, i.e., those that exhibit the lowest M values. Shown is the stability ranking of the reference genes in all samples. Genes are ranked from left to right in order of increasing expression stability (decreasing M value)