The result is consistent with our previous work in rats that showed that the expression of miR‐20a gradually decreased in the late stage of foetal lung development.12 Given these results, which were further validated by real‐time qPCR, and in view of the role of PS in RDS, the association between miR‐20a and RDS and the role of miR‐20a in lung development, we further explored the role of miR‐20a‐5p in pulmonary surfactant gene expression. The gene discussed is PRB2; the disease is newborn respiratory distress syndrome.