Sensorineural hearing defect and goiter are common features of Pendred's 
syndrome. The clinical diagnosis of Pendred's syndrome remains difficult because 
of the lack of sensitivity and specificity of the thyroid signs. The 
identification of PDS as the causative gene allowed molecular screening and 
enabled a re-evaluation of the syndrome to identify potential diagnostic 
characteristics. This report presents the clinical and genotypic findings of 30 
French families, for whom a diagnosis of Pendred's syndrome had been made. 
Twenty-seven families had at least one mutated allele. Twenty-eight different 
mutations were identified, 11 of which had never been previously reported. The 
main clinical characteristics were: early hearing loss, fluctuation in terms of 
during deafness evolution, and the presence of an enlarged vestibular aqueduct.