SALL1 and Townes-Brocks syndrome: Townes-Brocks' syndrome (TBS) is a rare autosomal dominant inherited malformation syndrome that is characterized by anal, renal, limb and ear abnormalities, and is uniquely associated with mutations in the SALL1 gene, which encodes a transcription factor called Spalt-like 1 [Spalt major (Salm) in flies].