Interestingly, a missense variant in IL10RA increases the risk of adult onset polygenic inflammatory bowel disease (IBD)3, while regulatory variants that boost IL-10 expression are associated with reduced IBD susceptibility.4 These data suggest an impact of IL-10 signalling in both early-onset and adult IBD but it remains possible that the absence of IL-10 signaling in infancy has a more profound effect on gut immune homeostasis because of a developmental window of susceptibility. The gene discussed is IL10; the disease is inflammatory bowel disease.