Several genetic diseasesh ave been mapped to the region of
the X chromosome to which GluR3 has been localized (q25-
26). The oculocerebralrenal syndrome of Lowe (OCRL) is manifest
by mental retardation, congenital cataract, and proximal
renal tubular acidosis (Lowe et al., 1952). Linkage analysis,
mapping with somatic cell hybrids, and long-range restriction
mapping together have successfully ordered a panel of Xq24-
26 markers with respect to the OCRL locus (Reilly et al., 1990).
Turner et al. (1989) described a family with intellectual handicap,
small testes, postpubertal gynecomastia, and skeletal abnormalities
and mapped the disorder with linkage analysis to
Xq26-27. Shiloh et al. (1990) used linkage analysis to map a
syndrome characterized by congenital nerve deafnessa nd albinism
to Xq26.3-27.1. The powerful role of glutamatergic synapsesin
synapsef ormation (Constantine-Patone t al., 1990)a nd
in excitotoxic death of neurons together with the expression of
GluR3 in cerebral cortex and cochlear ganglion raises the possibility
that a mutation of GluR3 could contribute to these
disorders.