18 Identification of a Novel Nonsense Mutation in the Eya1 Gene Associated with Branchiootic/Branchio-Oto-Renal Syndrome.

The most frequent causes of chronic renal failure in the first two decades of life are due to urinary tract malformations. Branchio-oto-renal syndrome (BOR) [OMIM 113650] is an autosomal dominant developmental disorder of the kidney and urinary tract, accompanied with hearing loss and presenting with a wide intrafamilial variability and reduced penetrance. Dominant mutations in the human homologues of the Drosophila eyes absent gene (EYA1) are frequently the cause of BOR and BO syndromes. EYA1 encodes a 559-amino acid polypeptide with a predicted molecular mass of 61.2 kD. Mutational analysis revealed a novel nonsense mutation in EYA1 as the cause of BOR in this family.