Principal component analysis and hierarchical clustering.

<p>miRNA (panel A) and mRNA expression (panel B) were analyzed in mesenteric arteries from WKY and SHR sublines at 6 weeks and 5 months of age. A clear clustering of age groups was observed, indicating strong age-related gene expression. Note that in panel A, the WKY/NHsd (5 months) stands out. In panel B, WKY/Tac at 6 weeks of age clusters with the WKY groups of 5 months of age. WKY and SHR less clearly separate, indicating a weaker relationship of gene expression with blood pressure. PC: principal component. Numbers in brackets: contribution of the principal component to variability in the data, given as percentage.