Figure 2.

Principal component analysis of the samples at birth. The closed circles correspond to infants who did not develop bronchopulmonary dysplasia (BPD) and the open circles to those who did develop BPD. The centroid of the ellipsoid hull for each subgroup is illustrated with a symbol over-struck with an X (circle for controls and square for BPD). This plot illustrates the limited separation of these samples from the transcriptome-wide perspective. P > 0.05 for t-test in each of the principal components.