A novel form of autosomal recessive pure hereditary spastic paraplegia maps to chromosome 13q14.
BACKGROUND
Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous disorder characterized by a progressive weakening and spasticity of the lower limbs. HSP is classified according to the presence or absence of accompanying neurologic problems and by the mode of inheritance. Currently, 17 loci have been linked to the various forms of HSP.


OBJECTIVE
To determine the chromosomal location of a gene causing pure autosomal recessive spastic paraplegia.


METHODS
Genotyping using fluorescently labeled microsatellite markers was performed on three affected individuals and three unaffected individuals from a family displaying pure autosomal recessive HSP (ARHSP) and sensorineural deafness. All family members were then included in the analysis to narrow the genetic interval. Candidate genes were screened for the presence of mutations by heteroduplex analysis.


RESULTS
The paraplegic trait linked to a 1.8-Mb region of chromosome 13q14 flanked by the FLJ11712 gene and the microsatellite marker D13S270. The deafness did not link to this region and did not cosegregate with the paraplegic trait.


CONCLUSIONS
The HSP that this family had represents a novel genetic form of pure ARHSP as no other form of HSP (autosomal dominant or recessive) has been linked to chromosome 13.
Hodgkinson
C A
CA
Genetics Department, King Faisal Specialist Hospital and Research Centre Riyadh, Kingdom of Saudi Arabia. hodgkinson@kfshrc.edu.sa
Bohlega
S
S
Abu-Amero
S N
SN
Cupler
E
E
Kambouris
M
M
Meyer
B F
BF
Bharucha
V A
VA
D000015:Abnormalities, Multiple / Q000235:genetics; D002648:Child; D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics*; D003638:Deafness / Q000235:genetics; D005808:Genes, Recessive / Q000235:genetics*; D005820:Genetic Testing; D015894:Genome, Human; D005838:Genotype; D020180:Heteroduplex Analysis; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D010375:Pedigree; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015419:Spastic Paraplegia, Hereditary / Q000235:genetics*