X-linked severe mental retardation and a progressive neurological disorder in a Belgian family: clinical and genetic studies.
The combination of X-linked mental retardation (XLMR) and neurological disorders occurs in a number of syndromes. Differential diagnosis mostly depends on clinical data and mapping of responsible genes by linkage analysis. We present a Belgian family with severe XLMR and a progressive neurological disorder with ataxia, spasticity and convulsions. Biochemical investigations, neuroimaging and neuropathology were normal. Linkage analysis pointed to region Xq27-28 as the probable locus for the genetic defect. The sequence of the L1CAM cDNA, a possible candidate gene, proved to be normal in the patients. This suggests the presence of a genetic factor on Xq27-28, different from L1CAM, which can lead to severe XLMR and a progressive neurological disorder.
Claes
S
S
Center for Human Genetics, University of Leuven, Belgium.
Devriendt
K
K
D'Adamo
P
P
Meireleire
J
J
Raeymaekers
P
P
Toniolo
D
D
Cassiman
J J
JJ
Fryns
J P
JP
D000293:Adolescent; D000328:Adult; D001530:Belgium; D002490:Central Nervous System / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D002874:Chromosome Mapping; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000032:analysis / Q000737:chemistry; D018450:Disease Progression; D005192:Family Health; D005796:Genes / Q000235:genetics; D008040:Genetic Linkage; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000235:genetics* / Q000473:pathology*; D007621:Karyotyping; D039841:Leukocyte L1 Antigen Complex; D008297:Male; D019006:Neural Cell Adhesion Molecules / Q000235:genetics; D010375:Pedigree; D012729:Sex Chromosome Aberrations; D014960:X Chromosome / Q000235:genetics*
D018076:DNA, Complementary; D005819:Genetic Markers; D039841:Leukocyte L1 Antigen Complex; D019006:Neural Cell Adhesion Molecules