title: Characterization of mutations in the gene doublecortin in patients with double cortex syndrome.
abstract: Mutations in the X-linked gene doublecortin, which encodes a protein with no dear structural homologues, are found in pedigrees in which affected females show "double cortex" syndrome (DC; also known as subcortical band heterotopia or laminar heterotopia) and affected males show X-linked lissencephaly. Mutations in doublecortin also cause sporadic DC in females. To determine the incidence of doublecortin mutations in DC, we investigated a cohort of eight pedigrees and 47 sporadic patients with DC for mutations in the doublecortin open reading frame as assessed by single-stranded conformational polymorphism analysis. Mutations were identified in each of the eight DC pedigrees (100%), and in 18 of the 47 sporadic DC patients (38%). Identified mutations were of two types, protein truncation mutations and single amino acid substitution mutations. However, pedigrees with DC displayed almost exclusively single amino acid substitution mutations, suggesting that patients with these mutations may have less of a reproductive disadvantage versus those patients with protein truncation mutations. Single amino acid substitution mutations were tightly clustered in two regions of the open reading frame, suggesting that these two regions are critical for the function of the Doublecortin protein.
authors.affiliation: Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Gleeson
authors.forename: S R
authors.initials: SR
authors.lastname: Minnerath
authors.forename: J W
authors.initials: JW
authors.lastname: Fox
authors.forename: K M
authors.initials: KM
authors.lastname: Allen
authors.forename: R F
authors.initials: RF
authors.lastname: Luo
authors.forename: S E
authors.initials: SE
authors.lastname: Hong
authors.forename: M J
authors.initials: MJ
authors.lastname: Berg
authors.forename: R
authors.initials: R
authors.lastname: Kuzniecky
authors.forename: P J
authors.initials: PJ
authors.lastname: Reitnauer
authors.forename: R
authors.initials: R
authors.lastname: Borgatti
authors.forename: A P
authors.initials: AP
authors.lastname: Mira
authors.forename: R
authors.initials: R
authors.lastname: Guerrini
authors.forename: G L
authors.initials: GL
authors.lastname: Holmes
authors.forename: C M
authors.initials: CM
authors.lastname: Rooney
authors.forename: S
authors.initials: S
authors.lastname: Berkovic
authors.forename: I
authors.initials: I
authors.lastname: Scheffer
authors.forename: E C
authors.initials: EC
authors.lastname: Cooper
authors.forename: S
authors.initials: S
authors.lastname: Ricci
authors.forename: R
authors.initials: R
authors.lastname: Cusmai
authors.forename: T O
authors.initials: TO
authors.lastname: Crawford
authors.forename: R
authors.initials: R
authors.lastname: Leroy
authors.forename: E
authors.initials: E
authors.lastname: Andermann
authors.forename: J W
authors.initials: JW
authors.lastname: Wheless
authors.forename: W B
authors.initials: WB
authors.lastname: Dobyns
authors.forename: C A
authors.initials: CA
authors.lastname: Walsh
mesh_terms: D001927:Brain Diseases / Q000235:genetics* / Q000473:pathology; D002540:Cerebral Cortex / Q000002:abnormalities* / Q000473:pathology; D004247:DNA / Q000032:analysis; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010375:Pedigree; D017354:Point Mutation; D018807:Polymorphism, Single-Stranded Conformational; D013577:Syndrome; D014960:X Chromosome / Q000235:genetics*