SLC26A4 and retinitis pigmentosa 1: In fact, for the syndromic forms for which deafness is the primary clinical manifestation, it is important to note that regular follow-up should be planned for all patients presenting with an apparently isolated deafness and carrying variants in the genes involved in USH or the SLC26A4 gene associated with PDS in order to anticipate the diagnosis of RP or thyroid dysfunction for USH and PDS, respectively.