- Survey of the frequency of USH1 gene mutations in a cohort of Usher patients shows the importance of cadherin 23 and protocadherin 15 genes and establishes a detection rate of above 90%. Roux, A.F., Faugère, V., Le Guédard, S., Pallares-Ruiz, N., Vielle, A., Chambert, S., Marlin, S., Hamel, C., Gilbert, B., Malcolm, S., Claustres, M. J. Med. Genet. (2006)