This joint effect is reflected in the adjusted probabilities for iron deficiency; higher predicted probabilities were found for children with H. pylori infection and higher levels of hepcidin (0.24 CI 95% 0.14–0.34), and for children without H. pylori infection and lower levels of hepcidin (0.24 CI 95% 0.14–0.33) (Figure 1). The gene discussed is HAMP; the disease is nutritional disorder.