An independent study also that examined BPD marker genes from bulk PBMCs identified 12 genes (RETN, EPHX2, CD27, NOSIP, APOA1BP, TMCO6, KLHL3, B3GALNT1, SLC9A4, PRKCD, ZNF791, and B3GNT2) that were differentially expressed in BPD (15). Here, CD27 is linked to bronchopulmonary dysplasia.