title: A locus for bilateral perisylvian polymicrogyria maps to Xq28.
abstract: Polymicrogyria (PMG) is one of a large group of human cortical malformations that collectively account for a significant percentage of patients with epilepsy, congenital neurological deficits, and intellectual disability. PMG is characterized by an excess of small gyri and abnormal cortical lamination. The most common distribution is bilateral, symmetrical, and maximal, in the region surrounding the sylvian fissures, and is known as "bilateral perisylvian polymicrogyria" (BPP). Most cases are sporadic, although several families have been observed with multiple affected members, usually following an X-linked inheritance pattern. Here we report the first genetic locus for BPP mapped by linkage analysis in five families. Linkage places the critical region for BPP at Xq28 (LOD score 3.08 in Xq28, distal to DXS8103 by multipoint analysis). We suggest that this region contains a gene that is necessary for correct neuronal organization and that the identification of this gene will both enhance our understanding of normal cortical development and accelerate the identification of other genes responsible for PMG.
authors.affiliation: INSERM U491, Faculté de Médecine de La Timone, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 5, France. laurent.villard@medecine.univ-mrs.fr
authors.forename: Laurent
authors.initials: L
authors.lastname: Villard
authors.forename: Karine
authors.initials: K
authors.lastname: Nguyen
authors.forename: Carlos
authors.initials: C
authors.lastname: Cardoso
authors.forename: Christa Lese
authors.initials: CL
authors.lastname: Martin
authors.forename: Ann M
authors.initials: AM
authors.lastname: Weiss
authors.forename: Mara
authors.initials: M
authors.lastname: Sifry-Platt
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Grix
authors.forename: John M
authors.initials: JM
authors.lastname: Graham
authors.forename: Robin M
authors.initials: RM
authors.lastname: Winter
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Leventer
authors.forename: William B
authors.initials: WB
authors.lastname: Dobyns
mesh_terms: D002540:Cerebral Cortex / Q000002:abnormalities* / Q000473:pathology / Q000503:physiopathology; D002874:Chromosome Mapping; D005260:Female; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D008126:Lod Score; D008279:Magnetic Resonance Imaging; D008297:Male; D009421:Nervous System Malformations / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D010375:Pedigree; D014960:X Chromosome / Q000235:genetics*