title: Linkage results on 11Q21-22 in Eastern Quebec pedigrees densely affected by schizophrenia.
abstract: The 11q21-22 region is of interest for schizophrenia because several candidate genes are located in this section of the genome. The 11q21-22 region, including DRD2, was surveyed by linkage analysis in a sample (N = 242) made of four large multigenerational pedigrees densely affected by schizophrenia (SZ) and eight others by bipolar disorder (BP). These pedigrees were ascertained in a large area of Eastern Quebec and Northern New Brunswick and are still being extended. Family members were administered a "consensus best-estimate diagnosis procedure" (DSM-III-R criteria) blind to probands and relatives' diagnosis and to pedigree assignment (SZ or BP). For linkage analysis, 11 microsatellite polymorphism (CA repeat) markers, located at 11q21-22, and comprising DRD2, were genotyped. Results show no evidence of a major gene for schizophrenia. However, a maximum lod score of 3.41 at the D11S35 locus was observed in an affected-only analysis of one large SZ family, pedigree 255. Whether or not the positive linkage trend in pedigree 255 reflects a true linkage for a small proportion of SZ needs to be confirmed through the extension of this kindred and through replication.
authors.affiliation: Centre de Recherche Université Laval Robert-Giffard, de la Canardière, Beauport, Québec, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Maziade
authors.forename: V
authors.initials: V
authors.lastname: Raymond
authors.forename: D
authors.initials: D
authors.lastname: Cliche
authors.forename: J P
authors.initials: JP
authors.lastname: Fournier
authors.forename: C
authors.initials: C
authors.lastname: Caron
authors.forename: Y
authors.initials: Y
authors.lastname: Garneau
authors.forename: L
authors.initials: L
authors.lastname: Nicole
authors.forename: P
authors.initials: P
authors.lastname: Marcotte
authors.forename: C
authors.initials: C
authors.lastname: Couture
authors.forename: C
authors.initials: C
authors.lastname: Simard
mesh_terms: D001483:Base Sequence; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics*; D017931:DNA Primers; D008040:Genetic Linkage; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D010375:Pedigree; D011792:Quebec; D012559:Schizophrenia / Q000235:genetics*
chemical_list: D017931:DNA Primers; D005819:Genetic Markers