Mapping genes for schizophrenia in the South Pacific
ARTICLE: "Genome-wide multipoint linkage analyses of multiplex schizophrenia pedigrees from the oceanic nation of Palau"
AUTHORS: B. Devlin, Silviu-Alin Bacanu, Kathryn Roeder, Fred Reimherr, Paul Wender, Brandi Galke, Denise Novasad, Allan Chu, Karen T.Cuenco, Seba Tiobek, Caleb Otto, William Byerley
Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA; Department of Statistics, Carnegie Mellon University, Pittsburgh, PA; Department of Psychiatry, University of Utah Medical Center, Salt Lake City, Utah; Department of Psychiatry, University of California, Irvine, CA; Department of Genetics, University of Pittsburgh, Pittsburgh, PA; Belau National Hospital, Korror, Palau.
Schizophrenia is a devastating neuropsychiatric disorder that afflicts 1% of the worldwide population. Remarkably, the prevalence of schizophrenia is the same throughout the world despite differing cultures and environments of most nations. It is also notable that the cardinal signs and symptoms of schizophrenia - hallucinations and delusions - are the same throughout the world. In addition, family, twin and adoption studies from different populations indicate genetic factors contribute substantially to susceptibility to this illness. Small, isolated populations can be useful for gene mapping for two reasons: the genetic causes of illness are typically less heterogeneous, and isolated populations often contain large extended multiplex pedigrees ideal for mapping genes. For these reasons, the investigators initiated a genetic study of schizophrenia in Palau, Micronesia. Palau, also termed Belau, which is located approximately 725 miles southwest of Guam in the South Pacific. Presentation and symptoms of schizophrenia are no different in Palau.
The study findings, published in the September issue of Molecular Psychiatry, indicate that the genetic factors are distinct for each of the 5 families. The findings were perhaps somewhat unexpected given the small population (roughly 20,000 individuals) and geographic isolation, but they reinforce the genetic complexities of schizophrenia and they demonstrate the usefulness of large extended pedigrees for gene mapping.