familial mental retardation associated with ataxia

the hereditary ataxias are a group of genetically defined neurological diseases which are characterized by heterogeneous clinical presentations. ataxia is defined as imbalance and lack of coordination. mental retardation associated with ataxia has been reported in some of the known and recently identified syndromes. in this review, we describe some known and novel genes that cause familial mental retardation associated with ataxia. we have investigated some consanguineous iranian families who suffer mental retardation, disturbed equilibrium, walking disability and some other symptoms. through autozygosity mapping, we identified an iranian family with a new deletion in the vldr gene known as the disequilibrium syndrome (des). also, we characterized a number of families with autosomal recessive mental retardation, ataxia and other symptoms.