HOXC4, one of the HOX genes, has been associated with the VACTERL association disease characterized by vertebral abnormities, anal atresia, cardiac defects, tracheal anomalies, esophageal atresia and renal abnormalities (Genecards database, http://www.genecards.org/). The gene discussed is HOXC4; the disease is Esophageal atresia.