Article

Nature and nurture in neuropsychiatric genetics: where do we stand?

Department of Psychiatry, Virginia Institute of Psychiatric and Behavioral Genetics, Richmond 23298, USA.
Dialogues in clinical neuroscience 03/2010; 12(1):7-23.
Source: PubMed

ABSTRACT Both genetic and nongenetic risk factors, as well as interactions and correlations between them, are thought to contribute to the etiology of psychiatric and behavioral phenotypes. Genetic epidemiology consistently supports the involvement of genes in liability. Molecular genetic studies have been less successful in identifying liability genes, but recent progress suggests that a number of specific genes contributing to risk have been identified. Collectively, the results are complex and inconsistent, with a single common DNA variant in any gene influencing risk across human populations. Few specific genetic variants influencing risk have been unambiguously identified, Contemporary approaches, however hold great promise to further elucidate liability genes and variants, as well as their potential inter-relationships with each other and with the environment. We will review the fields of genetic epidemiology and molecular genetics, providing examples from the literature to illustrate the key concepts emerging from this work.

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Available from: Brien Patrick Riley, Jul 29, 2015
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    • "The number of recent claims by social scientists to have discovered a statistically significant association between a particular common gene variant—either on its own or in conjunction with a particular environment—and complex, politically relevant behaviors warrants careful evaluation. This evaluation is particularly needed because the search for genes that could predict prevalent and devastating behavioral phenotypes such as schizophrenia and autism, not to mention global killers such as diabetes and hypertension, has to date been unsuccessful (Dick, Riley, and Kendler 2010; Franke, Neale, and Faraone 2009; Plomin and Davis 2009; Talmud et al. 2010). The purpose of this article is to undertake such an evaluation. "
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    • "Its cost to society in terms of health care demands and lost productivity is well documented (Rice 2009), as are the personal stories of lifelong anguish and suffering among SZ patients and their families. While both genetic and epigenetic factors are associated with a risk for developing this disorder (Dick et al. 2010), the etiology and pathophysiology of SZ remain incompletely understood. More than 50 years after the introduction of drugs that target its symptoms, the standard medications for SZ are at best modestly effective. "
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    • "It has proven difficult to identify genes that predispose to schizophrenia (Sullivan, 2005; Crow, 2008; Sanders et al., 2008; Sullivan, 2008a; Sullivan, 2008b; Need et al., 2009; Dick et al., 2010; Gejman et al., 2010), and many explanations for the missing heritability have been suggested (Manolio et al., 2009; Gershon et al., 2011). Thus it is not surprising that our SNP-wise analyses did not alter the excess risk associated with familial history of psychiatric disorder — in particular when taking a resolution of only 547,071 SNPs and a sample size of only 739 cases and 800 controls into account. "
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