Psychiatric genetics
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Psychiatric genetics · Apr 2013
Copy number variation findings among 50 children and adolescents with autism spectrum disorder.
Autism spectrum disorders (ASDs) are a heterogeneous group of neurodevelopment disorders with a complex genetic aetiology. The aim of this study was to identify copy number variations (CNVs) with a clinical significance for ASD. ⋯ This study identified five novel CNVs among the individuals. The causal relationship between identified CNVs and the ASD phenotype is not fully established. However, the genes involved are associated with ASD and/or other neuropsychiatric disorders, or implicated in synaptic and neuronal activity, thus suggesting clinical significance. Further identification of ASD-associated CNVs is required, together with a broad clinical characterization of affected individuals to identify genotype-phenotype correlations.
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Psychiatric genetics · Apr 2012
Data mining approaches for genome-wide association of mood disorders.
Mood disorders are highly heritable forms of major mental illness. A major breakthrough in elucidating the genetic architecture of mood disorders was anticipated with the advent of genome-wide association studies (GWAS). However, to date few susceptibility loci have been conclusively identified. The genetic etiology of mood disorders appears to be quite complex, and as a result, alternative approaches for analyzing GWAS data are needed. Recently, a polygenic scoring approach that captures the effects of alleles across multiple loci was successfully applied to the analysis of GWAS data in schizophrenia and bipolar disorder (BP). However, this method may be overly simplistic in its approach to the complexity of genetic effects. Data mining methods are available that may be applied to analyze the high dimensional data generated by GWAS of complex psychiatric disorders. ⋯ The performance of the classifiers in the test dataset was evaluated by comparing area under the receiver operating characteristic curves. Bayesian networks performed the best of all the data mining classifiers, but none of these did significantly better than the polygenic score approach. We further examined a subset of single-nucleotide polymorphisms (SNPs) in genes that are expressed in the brain, under the hypothesis that these might be most relevant to BP susceptibility, but all the classifiers performed worse with this reduced set of SNPs. The discriminative accuracy of all of these methods is unlikely to be of diagnostic or clinical utility at the present time. Further research is needed to develop strategies for selecting sets of SNPs likely to be relevant to disease susceptibility and to determine if other data mining classifiers that utilize other algorithms for inferring relationships among the sets of SNPs may perform better.
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Psychiatric genetics · Oct 2010
Selected summaries from the XVII World Congress of Psychiatric Genetics, San Diego, California, USA, 4-8 November 2009.
The XVII World Congress of Psychiatric Genetics, sponsored by The International Society of Psychiatric Genetics (ISPG) took place in San Diego, California from 4 to 8 November 2009. Approximately 550 participants gathered to discuss the latest molecular genetic findings relevant to serious mental illness, including schizophrenia, mood disorders, substance abuse, autism, and attention deficit disorder. Recent advances in the field were discussed, including the genome-wide association studies results, copy number variation (CNV) in the genome, genomic imaging, and large multicenter collaborations. The following report, written by junior travel awardees who were assigned sessions as rapporteurs represents some of the areas covered in oral presentation during the conference, and reports on some of the notable major new findings described at this 2009 World Congress of Psychiatric Genetics.
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Psychiatric genetics · Aug 2010
Catechol-O-methyltransferase modulation of cortisol secretion in psychiatrically at-risk and healthy adolescents.
Recent research implicates the catechol-O-methyltransferase (COMT) ValMet polymorphism in stress sensitivity, through modulation of hypothalamic-pituitary-adrenal (HPA) function. In healthy samples, Met homozygosity has been associated with greater HPA activity (i.e., cortisol) and stress sensitivity, though findings are mixed among clinical samples. To date, there are no reports examining baseline or longitudinal changes in HPA activity as a function of COMT genotype in youth. This study tested the hypothesis that COMT genotype would be associated with cortisol secretion in normal and at-risk adolescents; specifically, that COMT genotype would be linked in a dose-response manner such that Met homozygotes would have the highest salivary cortisol levels, followed by heterozygotes, then Val homozygotes. In addition, this study examined the relation of COMT genotype with longitudinal changes in cortisol. ⋯ Findings are discussed with respect to COMT genotype as a potential genetic indicator of psychiatric risk that modulates developmental changes in HPA activity.
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Psychiatric genetics · Oct 2007
The association between delirium and the apolipoprotein E epsilon4 allele in the elderly.
As not all patients with similar risk factors and eliciting conditions develop delirium; it may be hypothesized that genetic variation may play a role in the risk of delirium. On the basis of the relationship between dementia, respectively reduced cholinergic activity, and the APOE epsilon4-allele, and the similarities between dementia and delirium in reduced cholinergic activity, the APOE epsilon4-allele is a rational candidate-gene for delirium. This study examined the association between APOE epsilon4-allele and delirium in elderly patients. ⋯ We found no convincing evidence that carriers of the APOE epsilon4-allele have a higher risk of delirium.