Mental Retardation With Optic Atrophy, Deafness, And Seizures

Clinical Features

Gustavson et al. (1993) described a 'new' X-linked mental retardation syndrome in 7 male children in 6 separate sibships in 2 generations of a family. The affected individuals were genealogically connected through females who were presumably carriers. In addition to severe retardation, the syndrome included microcephaly, optic atrophy with severely impaired vision or blindness, severe hearing defect, spasticity, epileptic seizures, restricted movement of the large joints, and death in infancy or early childhood.

Mapping

Malmgren et al. (1993) performed linkage analysis in 21 members, including 2 affected males, of the family reported by Gustavson et al. (1993). They found linkage with a hypervariable short tandem repeat at locus DXS294 at Xq26; peak two-point lod score = 3.35 at theta = 0.0. At least two other mental retardation syndromes mapped to the same region: Borjeson syndrome (301900) and Pettigrew syndrome (304340).