title: Genomewide multipoint linkage analysis of seven extended Palauan pedigrees with schizophrenia, by a Markov-chain Monte Carlo method.
abstract: Palauans are an isolated population in Micronesia with lifetime prevalence of schizophrenia (SCZD) of 2%, compared to the world rate of approximately 1%. The possible enrichment for SCZD genes, in conjunction with the potential for reduced etiological heterogeneity and the opportunity to ascertain statistically powerful extended pedigrees, makes Palauans a population of choice for the mapping of SCZD genes. We have used a Markov-chain Monte Carlo method to perform a genomewide multipoint analysis in seven extended pedigrees from Palau. Robust multipoint parametric and nonparametric linkage (NPL) analyses were performed under three nested diagnostic classifications-core, spectrum, and broad. We observed four regions of interest across the genome. Two of these regions-on chromosomes 2p13-14 (for which, under core diagnostic classification, NPL=6.5 and parametric LOD=4.8) and 13q12-22 (for which, under broad diagnostic classification, parametric LOD=3.6, and, under spectrum diagnostic classification, parametric LOD=3.5)-had evidence for linkage with genomewide significance, after correction for multiple testing; with the current pedigree resource and genotyping, these regions are estimated to be 4.3 cM and 19.75 cM in size, respectively. A third region, with intermediate evidence for linkage, was identified on chromosome 5q22-qter (for which, under broad diagnostic classification, parametric LOD=2.5). The fourth region of interest had only borderline suggestive evidence for linkage (on 3q24-28; for this region, under broad diagnostic classification, parametric LOD=2.0). All regions exhibited evidence for genetic heterogeneity. Our findings provide significant evidence for susceptibility loci on chromosomes 2p13-14 and 13q12-22 and support both a model of genetic heterogeneity and the utility of a broader set of diagnostic classifications in the population from Palau.
authors.affiliation: Genetic Epidemiology, Department of Medical Informatics, University of Utah School of Medicine, Salt Lake City, UT, USA. nicki@genepi.med.utah.edu
authors.forename: N J
authors.initials: NJ
authors.lastname: Camp
authors.forename: S L
authors.initials: SL
authors.lastname: Neuhausen
authors.forename: J
authors.initials: J
authors.lastname: Tiobech
authors.forename: A
authors.initials: A
authors.lastname: Polloi
authors.forename: H
authors.initials: H
authors.lastname: Coon
authors.forename: M
authors.initials: M
authors.lastname: Myles-Worsley
mesh_terms: D002874:Chromosome Mapping / Q000379:methods*; D002877:Chromosomes, Human / Q000235:genetics*; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D002895:Chromosomes, Human, Pair 5 / Q000235:genetics; D005260:Female; D005799:Genes, Dominant; D005808:Genes, Recessive; D018740:Genetic Heterogeneity; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006801:Humans; D008126:Lod Score; D008297:Male; D008390:Markov Chains; D008849:Micronesia / Q000453:epidemiology; D008957:Models, Genetic; D009010:Monte Carlo Method; D010375:Pedigree; D011581:Psychological Tests; D012559:Schizophrenia / Q000453:epidemiology / Q000235:genetics*