An extremely rare condition (only 200 cases have been identified worldwide), in which children have two or more of the following problems: malformations of the anus, hand deformities, external ear abnormalities, and nerve-related deafness. These malformations can range from minor to severe, and individuals may not have all of them.

Learn more about Townes-Brocks syndrome in Related Articles:  About First and Second Pharyngeal Arch Syndromes