While the immediate symptoms of immunoglobulin E (IgE) mediated CMA are easily recognized, the diagnosis of non-IgE mediated CMA is often a challenge because of the delayed symptom onset and overlap with common functional gastrointestinal disorders manifestations such as infantile colic, gastro-esophageal reflux (disease) or infections [2,3]. This evidence concerns the gene IGHE and gastroesophageal reflux disease.