Figure 1.

Evolution of idiopathic pulmonary fibrosis (IPF) transcriptome analysis. The progression of IPF transcriptomic research is that of increased complexity, more genes studied, more sample studied, and more detailed phenotypes. In the early days, a few thousand genes were analyzed on a small number of samples and limited analytical approaches. During the emerging period investigators studied tens of samples, mostly on microarrays that profiled of all protein coding mRNAs. In the established period, the numbers of samples are in hundreds, all transcribed RNA is measured, and analytical methods are sophisticated.