The Usher syndromes are genetically distinct disorders which share spe
cific phenotypic characteristics. This paper describes a set of clinic
al criteria recommended for the diagnosis of Usher syndrome type I and
Usher syndrome type II. These criteria have been adopted by the Usher
Syndrome Consortium and are used in studies reported by members of th
is Consortium. (C) 1994 Wiley-Liss, Inc.