How to diagnose Townes-Brocks syndrome ?
How is Townes-Brocks syndrome diagnosed? Townes-Brocks syndrome is diagnosed clinically based on the presence of the following: Imperforate anus Abnormally shaped ears Typical thumb malformations (preaxial polydactyly, triphalangeal thumbs which have three bones in them, much like the fingers, instead of the normal two, hypoplastic or underdeveloped thumbs) without shortening of the radius (the larger of the two bones in the forearm) SALL1 is the only gene known to be associated with Townes-Brocks syndrome. Detection of a SALL1 mutation confirms the diagnosis. Genetic testing is available on a clinical basis.