Figure 5

Dendrogram plots. Visual inspection of two merged data sets using dendrograms plots. In these dendrogram plots samples are labeled by a number corresponding to the study they originate from. For clarity purposes only 40 randomly selected samples are used to perform the hierarchical clustering. On the left the two data sets are merged without any transformation and on the right the two data sets are merged by using the COMBAT method. In the right plot it can be seen that samples originating from different studies are mixed, while on the left they are grouped per study.