Early-onset chronic autoimmune/inflammatory diseases, such as type I diabetes, celiac disease and paediatric inflammatory bowel disease (particularly Crohn's disease), are associated with growth impairment in children/teenagers, although other factors contribute, including nutritional deficit and/or abnormality of the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis [27]–[29]. This evidence concerns the gene GH1 and inflammatory bowel disease.