Reexamination of our panel of 14 PDA cell lines by immunoblot (Figure 2A) and qRT-PCR (Figure 1—figure supplement 1H) for mesenchymal markers - ZEB1, ZEB2, Vimentin (VIM), SNAI1, SNAI2, N-Cadherin (CDH2) - and epithelial markers – E-Cadherin (CDH1), Epithelial splicing regulatory protein 1 and 2 (ESRP1, ESRP2) – enabled classification into EMT low and EMT high groups. This evidence concerns the gene SNAI2 and Patent ductus arteriosus.