Epidemiologists have shown data that epigenetic marks are caused by environmental influences during early development, and that they can effect phenotypic expression throughout one's lifetime. In work published this week in PNAS, they used mass spec analysis to measure DNA methylation across a sample of 60 people who were prenatally exposed to famine during the Dutch Hunger Winter in 1944-45. Compared to their same-sex siblings, they had less DNA methylation of the imprinted IGF2 gene. Insulin-like growth factor II is key factor in human growth and development. In another paper, scientists developed a method to predict human microRNAs without cross-species conservation. Specifically, they found both P-2 and P-27–5p are novel miRNAs, and that CREB3L3, which encodes cAMP-responsive element binding protein 3-like 3, is a target gene of P-2, and LAMB3, which encodes laminin β3, is a target gene of P-27–5p.