Therefore, two explanations have been proposed for the mechanism by which EAC may appear; i) cellular expression of brachyury could be activated by acquired genetic or epigenetic alterations of the T-brachyury gene, driving the development of tumor cells with notochordal differentiation [8], and ii) activation in progenitor cells of a set of genes important for early embryonic development, leading to subsequent differentiation into a notochordal phenotype [9]. The gene discussed is TBX1; the disease is neoplasm.