Linkage of ‘pure’ autosomal recessive familial spastic paraplegia to chromosome 8 markers and evidence of genetic locus heterogeneity

Abstract

‘Pure’ familial spastic paraplegias (FSP) are neuro-degenerative disorders that are clinically characterized by progressive spastlcity of the lower limbs and are inherited as autosomal dominant (DFSP) or autosomal recessive (RFSP) traits. The primary defect in FSP Is unknown. Genetic linkage analysis was applied to five RFSP families from Tunisia. In four of these five families tight linkage of the RFSP locus was established to the chromosome 8 markers, D8S260, D8S166, D8S285, PLAT, and D8S279. The RFSP locus in the fifth family was not linked to these markers which provided evidence of genetic locus heterogeneity In RFSP. Identification of the RFSP gene on chromosome 8 will help in understanding the genetic factors in motor neuron degeneration.