A whole-genome scan in a large family with leukodystrophy and oligodontia reveals linkage to 10q22.
Dentoleukoencephalopathies with autosomal recessive inheritance are very rare. Recently, a large inbred Syrian pedigree was reported with oligodontia in association with a degenerative neurologic condition characterized by progressive ataxia and pyramidal syndrome and abnormalities in the white matter and cortical atrophy. A whole-genome screening of this family using 382 microsatellite markers was completed, but no evidence was found of linkage to any chromosomal region. A genome-wide linkage analysis using the 260K single nucleotide polymorphism Affymetrix array was then undertaken and a maximum multipoint logarithm of the odds score of 5.66 (NPL score = 7.65) was detected on chromosome 10q22 region. This genomic interval contains 95 known genes including the Prosaposin gene (PSAP) responsible for metachromatic leukodystrophy, which was excluded. Seventeen additional candidate genes were tested and excluded. Sequencing of the whole candidate locus is in progress and should allow the identification of the causative gene in this rare disease, thereby improving the understanding of the physiopathology of this disease.
Chouery
Eliane
E
Unité de Génétique Médicale et laboratoire associé INSERM à l'unité UMR_S 910, Faculté de Médecine, Université Saint-Joseph, Beirut, Lebanon.
Delague
Valérie
V
Jalkh
Nadine
N
Salem
Nabiha
N
Kfoury
Jessy
J
Rodriguez
Diana
D
Chabrol
Brigitte
B
Boespflug-Tanguy
Odile
O
Lévy
Nicolas
N
Serre
Jean Louis
JL
Mégarbané
André
A
D000293:Adolescent; D017668:Age of Onset; D000848:Anodontia / Q000235:genetics*; D002648:Child; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics*; D003241:Consanguinity; D005260:Female; D005808:Genes, Recessive; D055106:Genome-Wide Association Study; D020279:Hereditary Central Nervous System Demyelinating Diseases / Q000235:genetics*; D006801:Humans; D008126:Lod Score; D008297:Male; D018895:Microsatellite Repeats; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide; D013593:Syria