A SYNDROME OF SEVERE MENTAL-RETARDATION, SPASTICITY, AND TAPETORETINAL DEGENERATION LINKED TO CHROMOSOME 15Q24

Nine affected individuals are described from a large extended Pakistan i family manifesting a syndrome characterized by a triad of varying de grees of spasticity, severe mental retardation, and visual impairment resulting from tapetoretinal degeneration. in all cases, the parents w ere at least first cousins, since there was complex consanguinity with in the pedigree. The clinical features differ from previously reported syndromes involving pigmentary retinal degeneration and appear to rep resent a new recessively inherited neurodegenerative condition. Linkag e to a 4-5 cM-region between markers D15S211 and D15S152 on 15q24 has been established by autozygosity mapping.