The genetic basis of bipolar disorder has long been thought to be complex, with the potential involvement of multiple genes, but methods to analyze populations with respect to this complexity have ...only recently become available. We have carried out a genome-wide association study of bipolar disorder by genotyping over 550,000 single-nucleotide polymorphisms (SNPs) in two independent case-control samples of European origin. The initial association screen was performed using pooled DNA, and selected SNPs were confirmed by individual genotyping. While DNA pooling reduces power to detect genetic associations, there is a substantial cost saving and gain in efficiency. A total of 88 SNPs, representing 80 different genes, met the prior criteria for replication in both samples. Effect sizes were modest: no single SNP of large effect was detected. Of 37 SNPs selected for individual genotyping, the strongest association signal was detected at a marker within the first intron of diacylglycerol kinase eta (DGKH; P=1.5 x 10(-8), experiment-wide P<0.01, OR=1.59). This gene encodes DGKH, a key protein in the lithium-sensitive phosphatidyl inositol pathway. This first genome-wide association study of bipolar disorder shows that several genes, each of modest effect, reproducibly influence disease risk. Bipolar disorder may be a polygenic disease.
•Bipolar disorder is associated with a high risk of suicide death.•Most people who commit suicide are psychiatric patients, most of whom have affective disorders.•Some variables (demographic, ...personal, clinics, comorbility, biological - genetic) increase the risk of suicide.
Completed suicide is a major cause of death in bipolar disorder (BD) patients.
The aim of this paper is to provide an overall review of the existing literature of completed suicide in BD patients, including clinical and genetic data
We performed a systematic review of English and non-English articles published on MEDLINE/PubMed, PsycInfo and Cochrane database (1970–2017). Additional studies were identified by contacting clinical experts, searching bibliographies, major textbooks and website of World Health Organization. Initially we did a broad search for the association of bipolar disorder and suicide and we were narrowing the search in terms included “bipolar disorder” and “completed suicide”.
Inclusion criteria were articles about completed suicide in patients with BD. Articles exclusively focusing on suicide attempts and suicidal behaviour have been excluded. We used PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) consensus for drafting this systematic review.
The initial search generated 2806 articles and a total of 61 meeting our inclusion criteria. We reviewed epidemiological data, genetic factors, risk factors and treatment of completed suicide in BD. Suicide rates in BD vary between studies but our analyses show that they are approximately 20-30-fold greater than in general population. The highest risk of successful suicide was observed in BD-II subjects. The heritability of completed suicide is about 40% and some genes related to major neurotransmitter systems have been associated with suicide. Lithium is the only treatment that has shown anti-suicide potential.
The most important limitation of the present review is the limited existing literature on completed suicide in BD.
BD patients are at high risk for suicide. It is possible to identify some factors related to completed suicide, such as early onset, family history of suicide among first-degree relatives, previous attempted suicides, comorbidities and treatment. However it is necessary to promote research on this serious health problem.
Two recent reports have highlighted ANK3 as a susceptibility gene for bipolar disorder (BD). We first reported association between BD and the ANK3 marker rs9804190 in a genome-wide association study ...(GWAS) of two independent samples (Baum et al., 2008). Subsequently, a meta-analysis of GWAS data based on samples from the US and the UK reported association with a different ANK3 marker, rs10994336 (Ferreira et al., 2008). The markers lie about 340 kb apart in the gene. Here, we test both markers in additional samples and characterize the contribution of each marker to BD risk. Our previously reported findings at rs9804190, which had been based on DNA pooling, were confirmed by individual genotyping in the National Institute of Mental Health (NIMH) waves 1-4 (P=0.05; odds ratio (OR)=1.24) and German (P=0.0006; OR=1.34) samples. This association was replicated in an independent US sample known as NIMH wave 5 (466 cases, 212 controls; P=0.017; OR=1.38). A random-effects meta-analysis of all three samples was significant (P=3 x 10(-6); OR=1.32), with no heterogeneity. Individual genotyping of rs10994336 revealed a significant association in the German sample (P=0.0001; OR=1.70), and similar ORs in the NIMH 1-4 and NIMH 5 samples that were not significant at the P<0.05 level. Meta-analysis of all three samples supported an association with rs10994336 (P=1.7 x 10(-5); OR=1.54), again with no heterogeneity. There was little linkage disequilibrium between the two markers. Further analysis suggested that each marker contributed independently to BD, with no significant marker x marker interaction. Our findings strongly support ANK3 as a BD susceptibility gene and suggest true allelic heterogeneity.
Meta-analyses of bipolar disorder (BD) genome-wide association studies (GWAS) have identified several genome-wide significant signals in European-ancestry samples, but so far account for little of ...the inherited risk. We performed a meta-analysis of ∼750,000 high-quality genetic markers on a combined sample of ∼14,000 subjects of European and Asian-ancestry (phase I). The most significant findings were further tested in an extended sample of ∼17,700 cases and controls (phase II). The results suggest novel association findings near the genes TRANK1 (LBA1), LMAN2L and PTGFR. In phase I, the most significant single nucleotide polymorphism (SNP), rs9834970 near TRANK1, was significant at the P=2.4 × 10(-11) level, with no heterogeneity. Supportive evidence for prior association findings near ANK3 and a locus on chromosome 3p21.1 was also observed. The phase II results were similar, although the heterogeneity test became significant for several SNPs. On the basis of these results and other established risk loci, we used the method developed by Park et al. to estimate the number, and the effect size distribution, of BD risk loci that could still be found by GWAS methods. We estimate that >63,000 case-control samples would be needed to identify the ∼105 BD risk loci discoverable by GWAS, and that these will together explain <6% of the inherited risk. These results support previous GWAS findings and identify three new candidate genes for BD. Further studies are needed to replicate these findings and may potentially lead to identification of functional variants. Sample size will remain a limiting factor in the discovery of common alleles associated with BD.
To identify bipolar disorder (BD) genetic susceptibility factors, we conducted two genome-wide association (GWA) studies: one involving a sample of individuals of European ancestry (EA; n=1001 cases; ...n=1033 controls), and one involving a sample of individuals of African ancestry (AA; n=345 cases; n=670 controls). For the EA sample, single-nucleotide polymorphisms (SNPs) with the strongest statistical evidence for association included rs5907577 in an intergenic region at Xq27.1 (P=1.6 x 10(-6)) and rs10193871 in NAP5 at 2q21.2 (P=9.8 x 10(-6)). For the AA sample, SNPs with the strongest statistical evidence for association included rs2111504 in DPY19L3 at 19q13.11 (P=1.5 x 10(-6)) and rs2769605 in NTRK2 at 9q21.33 (P=4.5 x 10(-5)). We also investigated whether we could provide support for three regions previously associated with BD, and we showed that the ANK3 region replicates in our sample, along with some support for C15Orf53; other evidence implicates BD candidate genes such as SLITRK2. We also tested the hypothesis that BD susceptibility variants exhibit genetic background-dependent effects. SNPs with the strongest statistical evidence for genetic background effects included rs11208285 in ROR1 at 1p31.3 (P=1.4 x 10(-6)), rs4657247 in RGS5 at 1q23.3 (P=4.1 x 10(-6)), and rs7078071 in BTBD16 at 10q26.13 (P=4.5 x 10(-6)). This study is the first to conduct GWA of BD in individuals of AA and suggests that genetic variations that contribute to BD may vary as a function of ancestry.
To investigate potential correlations between objective CBCT image parameters and accuracy in endodontic working length determination ex vivo. Contrast-to-noise ratio (CNR) and spatial resolution ...(SR) as fundamental objective image parameters were examined using specific phantoms in seven different CBCT machines. Seven experienced observers were instructed and calibrated. The order of the CBCTs was randomized for each observer and observation. To assess intra-operator reproducibility, the procedure was repeated within six weeks with a randomized order of CBCT images. Multivariate analysis (MANOVA) did not reveal any influence of the combined image quality factors CNR and SR on measurement accuracy. Inter-operator reproducibility as assessed between the two observations was poor, with a mean intra-class correlation (ICC) of 0.48 (95%-CI 0.38, 0.59) for observation No. 1. and 0.40 (95%-CI 0.30, 0.51) for observation No. 2. Intra-operator reproducibility pooled over all observers between both observations was only moderate, with a mean ICC of 0.58 (95%-CI 0.52 to 0.64). Within the limitations of the study, objective image quality measures and exposure parameters seem not to have a significant influence on accuracy in determining endodontic root canal lengths in CBCT scans. The main factor of variance is the observer.
The final fate of massive stars, and the nature of the compact remnants they leave behind (black holes and neutron stars), are open questions in astrophysics. Many massive stars are stripped of their ...outer hydrogen envelopes as they evolve. Such Wolf-Rayet stars
emit strong and rapidly expanding winds with speeds greater than 1,000 kilometres per second. A fraction of this population is also helium-depleted, with spectra dominated by highly ionized emission lines of carbon and oxygen (types WC/WO). Evidence indicates that the most commonly observed supernova explosions that lack hydrogen and helium (types Ib/Ic) cannot result from massive WC/WO stars
, leading some to suggest that most such stars collapse directly into black holes without a visible supernova explosion
. Here we report observations of SN 2019hgp, beginning about a day after the explosion. Its short rise time and rapid decline place it among an emerging population of rapidly evolving transients
. Spectroscopy reveals a rich set of emission lines indicating that the explosion occurred within a nebula composed of carbon, oxygen and neon. Narrow absorption features show that this material is expanding at high velocities (greater than 1,500 kilometres per second), requiring a compact progenitor. Our observations are consistent with an explosion of a massive WC/WO star, and suggest that massive Wolf-Rayet stars may be the progenitors of some rapidly evolving transients.
Abstract The hopes for readily implementable precision medicine are high. For many complex disorders, such as bipolar disorder, these hopes critically hinge on tangible successes in pharmacogenetics ...of treatment response or susceptibility to adverse events. In this article, we review the current state of pharmacogenomics of bipolar disorder including latest results from candidate genes and genome-wide association studies. The majority of studies focus on response to lithium treatment. Although a host of genes has been studied, hardly any replicated findings have emerged so far. Very small samples sizes and heterogeneous phenotype definition may be considered the major impediments to success in this field. Drawing from current experiences and successes in studies on diagnostic psychiatric phenotypes, we suggest several approaches for our way forward.
One hundred years after its conceptual definition as 'Dementia Praecox' by Emil Kraepelin, schizophrenia is still a serious psychiatric illness that affects young adults and leads to disability in at ...least half of patients. The key treatment issue is partial or non-response, especially of negative symptoms. The illness is also associated with different degrees of cognitive dysfunction, particularly in verbal and working memory; the resulting functional impairment may lead to unemployment and an inability to maintain stable relationships. Patients' cognitive dysfunction led Kraepelin to the assumption that schizophrenia is a form of juvenile dementia caused by a degenerative process of the human brain. Postmortem studies and a plethora of imaging studies do not support the notion of a degenerative process, but such a process is supported by the recently published, largest genome-wide association study on schizophrenia. More than a 100 hits were described, converging on pathways that have a significant role in dopamine metabolism in immune modulation, calcium signalling and synaptic plasticity. This review suggests that research should focus on animal models based on risk genes like transcription factor 4 and study the effects of exposure to environmental stressors relevant for schizophrenia. The use of relevant end points like pre-pulse inhibition or cognitive dysfunction will allow us to gain an understanding of the molecular pathways in schizophrenia and consequently result in improved treatment options, especially for the disabling aspects of this illness.
Major mood disorders, which primarily include bipolar disorder and major depressive disorder, are the leading cause of disability worldwide and pose a major challenge in identifying robust risk ...genes. Here, we present data from independent large-scale clinical data sets (including 29 557 cases and 32 056 controls) revealing brain expressed protocadherin 17 (PCDH17) as a susceptibility gene for major mood disorders. Single-nucleotide polymorphisms (SNPs) spanning the PCDH17 region are significantly associated with major mood disorders; subjects carrying the risk allele showed impaired cognitive abilities, increased vulnerable personality features, decreased amygdala volume and altered amygdala function as compared with non-carriers. The risk allele predicted higher transcriptional levels of PCDH17 mRNA in postmortem brain samples, which is consistent with increased gene expression in patients with bipolar disorder compared with healthy subjects. Further, overexpression of PCDH17 in primary cortical neurons revealed significantly decreased spine density and abnormal dendritic morphology compared with control groups, which again is consistent with the clinical observations of reduced numbers of dendritic spines in the brains of patients with major mood disorders. Given that synaptic spines are dynamic structures which regulate neuronal plasticity and have crucial roles in myriad brain functions, this study reveals a potential underlying biological mechanism of a novel risk gene for major mood disorders involved in synaptic function and related intermediate phenotypes.
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