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Background: Lithium (Li) remains the treatment of choice for bipolar disorders (BP). Its mood-stabilizing effects help reduce the long-term burden of mania, depression and suicide risk in patients with BP. It also has been shown to have beneficial effects on disease-associated conditions, including sleep and cardiovascular disorders. However, the individual responses to Li treatment vary within and between diagnostic subtypes of BP (e.g. BP-I and BP-II) according to the clinical presentation. Moreover, long-term Li treatment has been linked to adverse side-effects that are a cause of concern and non-adherence, including the risk of developing chronic medical conditions such as thyroid and renal disease. In recent years, studies by the Consortium on Lithium Genetics (ConLiGen) have uncovered a number of genetic factors that contribute to the variability in Li treatment response in patients with BP. Here, we leveraged the ConLiGen cohort (N = 2064) to investigate the genetic basis of Li effects in BP. For this, we studied how Li response and linked genes associate with the psychiatric symptoms and polygenic load for medical comorbidities, placing particular emphasis on identifying differences between BP-I and BP-II., Results: We found that clinical response to Li treatment, measured with the Alda scale, was associated with a diminished burden of mania, depression, substance and alcohol abuse, psychosis and suicidal ideation in patients with BP-I and, in patients with BP-II, of depression only. Our genetic analyses showed that a stronger clinical response to Li was modestly related to lower polygenic load for diabetes and hypertension in BP-I but not BP-II. Moreover, our results suggested that a number of genes that have been previously linked to Li response variability in BP differentially relate to the psychiatric symptomatology, particularly to the numbers of manic and depressive episodes, and to the polygenic load for comorbid conditions, including diabetes, hypertension and hypothyroidism., Conclusions: Taken together, our findings suggest that the effects of Li on symptomatology and comorbidity in BP are partially modulated by common genetic factors, with differential effects between BP-I and BP-II., (© 2024. The Author(s).)

Lithium is the gold standard treatment for bipolar disorder (BD). However, its mechanism of action is incompletely understood, and prediction of treatment outcomes is limited. In our previous multi-omics study of the Pharmacogenomics of Bipolar Disorder (PGBD) sample combining transcriptomic and genomic data, we found that focal adhesion, the extracellular matrix (ECM), and PI3K-Akt signaling networks were associated with response to lithium. In this study, we replicated the results of our previous study using network propagation methods in a genome-wide association study of an independent sample of 2039 patients from the International Consortium on Lithium Genetics (ConLiGen) study. We identified functional enrichment in focal adhesion and PI3K-Akt pathways, but we did not find an association with the ECM pathway. Our results suggest that deficits in the neuronal growth cone and PI3K-Akt signaling, but not in ECM proteins, may influence response to lithium in BD., (© 2024. The Author(s).)

The Human Phenotype Ontology (HPO) is a widely used resource that comprehensively organizes and defines the phenotypic features of human disease, enabling computational inference and supporting genomic and phenotypic analyses through semantic similarity and machine learning algorithms. The HPO has widespread applications in clinical diagnostics and translational research, including genomic diagnostics, gene-disease discovery, and cohort analytics. In recent years, groups around the world have developed translations of the HPO from English to other languages, and the HPO browser has been internationalized, allowing users to view HPO term labels and in many cases synonyms and definitions in ten languages in addition to English. Since our last report, a total of 2239 new HPO terms and 49235 new HPO annotations were developed, many in collaboration with external groups in the fields of psychiatry, arthrogryposis, immunology and cardiology. The Medical Action Ontology (MAxO) is a new effort to model treatments and other measures taken for clinical management. Finally, the HPO consortium is contributing to efforts to integrate the HPO and the GA4GH Phenopacket Schema into electronic health records (EHRs) with the goal of more standardized and computable integration of rare disease data in EHRs., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Lithium is regarded as the first-line treatment for bipolar disorder (BD), a severe and disabling mental health disorder that affects about 1% of the population worldwide. Nevertheless, lithium is not consistently effective, with only 30% of patients showing a favorable response to treatment. To provide personalized treatment options for bipolar patients, it is essential to identify prediction biomarkers such as polygenic scores. In this study, we developed a polygenic score for lithium treatment response (Li + PGS ) in patients with BD. To gain further insights into lithium's possible molecular mechanism of action, we performed a genome-wide gene-based analysis. Using polygenic score modeling, via methods incorporating Bayesian regression and continuous shrinkage priors, Li + PGS was developed in the International Consortium of Lithium Genetics cohort (ConLi + Gen: N = 2367) and replicated in the combined PsyCourse (N = 89) and BipoLife (N = 102) studies. The associations of Li + PGS and lithium treatment response - defined in a continuous ALDA scale and a categorical outcome (good response vs. poor response) were tested using regression models, each adjusted for the covariates: age, sex, and the first four genetic principal components. Statistical significance was determined at P < 0.05. Li + PGS was positively associated with lithium treatment response in the ConLi + Gen cohort, in both the categorical (P = 9.8 × 10 - 12 , R 2  = 1.9%) and continuous (P = 6.4 × 10 - 9 , R 2  = 2.6%) outcomes. Compared to bipolar patients in the 1 st decile of the risk distribution, individuals in the 10 th decile had 3.47-fold (95%CI: 2.22-5.47) higher odds of responding favorably to lithium. The results were replicated in the independent cohorts for the categorical treatment outcome (P = 3.9 × 10 - 4 , R 2  = 0.9%), but not for the continuous outcome (P = 0.13). Gene-based analyses revealed 36 candidate genes that are enriched in biological pathways controlled by glutamate and acetylcholine. Li + PGS may be useful in the development of pharmacogenomic testing strategies by enabling a classification of bipolar patients according to their response to treatment., (© 2023. The Author(s).)

Response to lithium varies widely between individuals with bipolar disorder (BD). Polygenic risk scores (PRSs) can uncover pharmacogenomics effects and may help predict drug response. Patients ( N = 2,510) with BD were assessed for long-term lithium response in the Consortium on Lithium Genetics using the Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder score. PRSs for attention-deficit/hyperactivity disorder (ADHD), major depressive disorder (MDD), and schizophrenia (SCZ) were computed using lassosum and in a model including all three PRSs and other covariates, and the PRS of ADHD (β = -0.14; 95% confidence interval [CI]: -0.24 to -0.03; p value = 0.010) and MDD (β = -0.16; 95% CI: -0.27 to -0.04; p value = 0.005) predicted worse quantitative lithium response. A higher SCZ PRS was associated with higher rates of medication nonadherence (OR = 1.61; 95% CI: 1.34-1.93; p value = 2e-7). This study indicates that genetic risk for ADHD and depression may influence lithium treatment response. Interestingly, a higher SCZ PRS was associated with poor adherence, which can negatively impact treatment response. Incorporating genetic risk of ADHD, depression, and SCZ in combination with clinical risk may lead to better clinical care for patients with BD., Competing Interests: Eduard Vieta has received grants and served as consultant, advisor, or CME speaker for the following entities: AB-Biotics, Allergan, Angelini, AstraZeneca, Bristol-Myers Squibb, Dainippon Sumitomo Pharma, Farmindustria, Ferrer, Forest Research Institute, Gedeon Richter, GlaxoSmithKline, Janssen, Lundbeck, Otsuka, Pfizer, Roche, Sanofi-Aventis, Servier, Shire, Sunovion, Takeda, the Brain and Behaviour Foundation, the Spanish Ministry of Science and Innovation (CIBERSAM), and the Stanley Medical Research Institute. Michael Bauer has received grants from the Deutsche Forschungsgemeinschaft and Bundesministeriums für Bildung und Forschung and served as consultant, advisor, or CME speaker for the following entities: Allergan, Aristo, Janssen, Lilly, Lundbeck, neuraxpharm, Otsuka, Sandoz, Servier, and Sunovion outside the submitted work. Sarah Kittel-Schneider has received grants and served as consultant, advisor, or speaker for the following entities: Medice Arzneimittel Pütter GmbH and Shire. Bernhard Baune has received grants and served as consultant, advisor, or CME speaker for the following entities: AstraZeneca, Bristol-Myers Squibb, Janssen, Lundbeck, Otsuka, Servier, the National Health and Medical Research Council, the Fay Fuller Foundation, and the James and Diana Ramsay Foundation. Tadafumi Kato received honoraria for lectures, manuscripts, and/or consultancy, from Kyowa Hakko Kirin Co., Ltd., Eli Lilly Japan K.K., Otsuka Pharmaceutical Co., Ltd., GlaxoSmithKline K.K., Taisho Toyama Pharmaceutical Co., Ltd., Dainippon Sumitomo Pharma Co., Ltd., Meiji Seika Pharma Co., Ltd., Pfizer Japan Inc., Mochida Pharmaceutical Co., Ltd., Shionogi & Co., Ltd., Janssen Pharmaceutical K.K., Janssen Asia Pacific, Yoshitomiyakuhin, Astellas Pharma Inc., Wako Pure Chemical Industries, Ltd., Wiley Publishing Japan, Nippon Boehringer Ingelheim Co. Ltd., Kanae Foundation for the Promotion of Medical Science, MSD K.K., Kyowa Pharmaceutical Industry Co., Ltd., and Takeda Pharmaceutical Co., Ltd. T.K. also received a research grant from Takeda Pharmaceutical Co., Ltd. Peter Falkai has received grants and served as consultant, advisor, or CME speaker for the following entities Abbott, GlaxoSmithKline, Janssen, Essex, Lundbeck, Otsuka, Gedeon Richter, Servier, and Takeda as well as the German Ministry of Science and the German Ministry of Health. Eva Reininghaus has received grants and served as consultant, advisor, or CME speaker for the following entities: Janssen and Institut Allergosan. Mikael Landén declares that, over the past 36 months, he has received lecture honoraria from Lundbeck and served as scientific consultant for EPID Research Oy; no other equity ownership, profit-sharing agreements, royalties, or patent. Kazufumi Akiyama has received consulting honoraria from Taisho Toyama Pharmaceutical Co., Ltd. The other authors have no other conflict of interest to disclose., (Copyright © 2021 by S. Karger AG, Basel.)

Background: Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools., Aims: To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics., Method: Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts., Results: Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = -0.34 years, s.e. = 0.08), major depression (β = -0.34 years, s.e. = 0.08), schizophrenia (β = -0.39 years, s.e. = 0.08), and educational attainment (β = -0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO., Conclusions: AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.

Lithium is the gold standard therapy for Bipolar Disorder (BD) but its effectiveness differs widely between individuals. The molecular mechanisms underlying treatment response heterogeneity are not well understood, and personalized treatment in BD remains elusive. Genetic analyses of the lithium treatment response phenotype may generate novel molecular insights into lithium's therapeutic mechanisms and lead to testable hypotheses to improve BD management and outcomes. We used fixed effect meta-analysis techniques to develop meta-analytic polygenic risk scores (MET-PRS) from combinations of highly correlated psychiatric traits, namely schizophrenia (SCZ), major depression (MD) and bipolar disorder (BD). We compared the effects of cross-disorder MET-PRS and single genetic trait PRS on lithium response. For the PRS analyses, we included clinical data on lithium treatment response and genetic information for n = 2283 BD cases from the International Consortium on Lithium Genetics (ConLi + Gen; www.ConLiGen.org ). Higher SCZ and MD PRSs were associated with poorer lithium treatment response whereas BD-PRS had no association with treatment outcome. The combined MET2-PRS comprising of SCZ and MD variants (MET2-PRS) and a model using SCZ and MD-PRS sequentially improved response prediction, compared to single-disorder PRS or to a combined score using all three traits (MET3-PRS). Patients in the highest decile for MET2-PRS loading had 2.5 times higher odds of being classified as poor responders than patients with the lowest decile MET2-PRS scores. An exploratory functional pathway analysis of top MET2-PRS variants was conducted. Findings may inform the development of future testing strategies for personalized lithium prescribing in BD., (© 2021. The Author(s).)

Bipolar affective disorder (BD) is a severe psychiatric illness, for which lithium (Li) is the gold standard for acute and maintenance therapies. The therapeutic response to Li in BD is heterogeneous and reliable biomarkers allowing patients stratification are still needed. A GWAS performed by the International Consortium on Lithium Genetics (ConLiGen) has recently identified genetic markers associated with treatment responses to Li in the human leukocyte antigens (HLA) region. To better understand the molecular mechanisms underlying this association, we have genetically imputed the classical alleles of the HLA region in the European patients of the ConLiGen cohort. We found our best signal for amino-acid variants belonging to the HLA-DRB1*11:01 classical allele, associated with a better response to Li (p < 1 × 10 -3 ; FDR < 0.09 in the recessive model). Alanine or Leucine at position 74 of the HLA-DRB1 heavy chain was associated with a good response while Arginine or Glutamic acid with a poor response. As these variants have been implicated in common inflammatory/autoimmune processes, our findings strongly suggest that HLA-mediated low inflammatory background may contribute to the efficient response to Li in BD patients, while an inflammatory status overriding Li anti-inflammatory properties would favor a weak response., (© 2021. The Author(s).)

Lithium is a first-line medication for bipolar disorder (BD), but only one in three patients respond optimally to the drug. Since evidence shows a strong clinical and genetic overlap between depression and bipolar disorder, we investigated whether a polygenic susceptibility to major depression is associated with response to lithium treatment in patients with BD. Weighted polygenic scores (PGSs) were computed for major depression (MD) at different GWAS p value thresholds using genetic data obtained from 2586 bipolar patients who received lithium treatment and took part in the Consortium on Lithium Genetics (ConLi + Gen) study. Summary statistics from genome-wide association studies in MD (135,458 cases and 344,901 controls) from the Psychiatric Genomics Consortium (PGC) were used for PGS weighting. Response to lithium treatment was defined by continuous scores and categorical outcome (responders versus non-responders) using measurements on the Alda scale. Associations between PGSs of MD and lithium treatment response were assessed using a linear and binary logistic regression modeling for the continuous and categorical outcomes, respectively. The analysis was performed for the entire cohort, and for European and Asian sub-samples. The PGSs for MD were significantly associated with lithium treatment response in multi-ethnic, European or Asian populations, at various p value thresholds. Bipolar patients with a low polygenic load for MD were more likely to respond well to lithium, compared to those patients with high polygenic load [lowest vs highest PGS quartiles, multi-ethnic sample: OR = 1.54 (95% CI: 1.18-2.01) and European sample: OR = 1.75 (95% CI: 1.30-2.36)]. While our analysis in the Asian sample found equivalent effect size in the same direction: OR = 1.71 (95% CI: 0.61-4.90), this was not statistically significant. Using PGS decile comparison, we found a similar trend of association between a high genetic loading for MD and lower response to lithium. Our findings underscore the genetic contribution to lithium response in BD and support the emerging concept of a lithium-responsive biotype in BD., (© 2020. The Author(s), under exclusive licence to Springer Nature Limited.)

Bipolar disorder is a heritable mental illness with complex etiology. We performed a genome-wide association study of 41,917 bipolar disorder cases and 371,549 controls of European ancestry, which identified 64 associated genomic loci. Bipolar disorder risk alleles were enriched in genes in synaptic signaling pathways and brain-expressed genes, particularly those with high specificity of expression in neurons of the prefrontal cortex and hippocampus. Significant signal enrichment was found in genes encoding targets of antipsychotics, calcium channel blockers, antiepileptics and anesthetics. Integrating expression quantitative trait locus data implicated 15 genes robustly linked to bipolar disorder via gene expression, encoding druggable targets such as HTR6, MCHR1, DCLK3 and FURIN. Analyses of bipolar disorder subtypes indicated high but imperfect genetic correlation between bipolar disorder type I and II and identified additional associated loci. Together, these results advance our understanding of the biological etiology of bipolar disorder, identify novel therapeutic leads and prioritize genes for functional follow-up studies.

Research to discover clinically useful predictors of lithium response in patients with bipolar disorder has largely found them to be elusive. We demonstrate here that detailed neuroimaging may have the potential to fill this important gap in mood disorder therapeutics. Lithium treatment and bipolar disorder have both been shown to affect anatomy of the hippocampi and amygdalae but there is no consensus on the nature of their effects. We aimed to investigate structural surface anatomy changes in amygdala and hippocampus correlated with treatment response in bipolar disorder. Patients with bipolar disorder ( N = 14) underwent lithium treatment, were classified by response status at acute and long-term time points, and scanned with 7 Tesla structural MRI. Large Deformation Diffeomorphic Metric Mapping was applied to detect local differences in hippocampal and amygdalar anatomy between lithium responders and non-responders. Anatomy was also compared to 21 healthy comparison participants. A patch of the ventral surface of the left hippocampus was found to be significantly atrophied in non-responders as compared to responders at the acute time point and was associated at a trend-level with long-term response status. We did not detect an association between response status and surface anatomy of the right hippocampus or amygdala. To the best of our knowledge, this is the first shape analysis of hippocampus and amygdala in bipolar disorder using 7 Tesla MRI. These results can inform future work investigating possible neuroimaging predictors of lithium response in bipolar disorder., Competing Interests: JRD reports that he is Chairperson of the Board of Directors of the National Network of Depression Centers and receives reimbursement for official travel (amounting to less than $1500 annually). He has been an unpaid consultant for Myriad Neuroscience (formerly Assurex Health, Inc.) on behalf of the NNDC for meetings in 2017 and 2019. The NNDC was compensated for his effort. JRD owns stock in CVS-Health (275 shares valued today at just over $20,000). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Athey, Ceritoglu, Tward, Kutten, DePaulo, Glazer, Goes, Kelsoe, Mondimore, Nievergelt, Rootes-Murdy, Zandi, Ratnanather and Mahon.)

Objectives: Mood disorders are among the most burdensome public health concerns. The National Network of Depression Centers (NNDC) is a nonprofit consortium of 26 leading clinical and academic member centers in the United States providing care for patients with mood disorders, including depression and bipolar disorder. The NNDC has established a measurement-based care program called the Mood Outcomes Program whereby participating sites follow a standard protocol to electronically collect patient-reported outcome assessments on depression, anxiety, and suicidal ideation in routine clinical care. This article describes the approaches taken to develop and implement the program., Methods: Since 2015, eight pilot sites have implemented the program and followed more than 10,000 patients. This pilot study presents descriptive statistics based on the first 24-month period of data collection., Results: In this sample, 58.6% of patients with bipolar disorder (N=849) and 57.5% of patients with unipolar depression (N=3,998) remained symptomatic at follow-up. Lifetime rates of planned or actual suicide attempts were high, ranging from 27.6% for patients with unipolar mood disorders to 33.5% for patients with bipolar disorder. Men, unmarried individuals, and those with comorbid anxiety had a poorer longitudinal course. This initial snapshot of clinical burden is consistent with public health data indicating that mood disorders are severely debilitating., Conclusions: This study demonstrates the potential of the Mood Outcomes Program to create a nationwide "learning health system" for mood disorders. This goal will be further realized as the program expands in reach and scope across additional NNDC sites.

This article focuses on some common dilemmas facing clinicians, patients, and families in managing the treatment of complicated mood disorders. Specifically, this article reviews the interaction of depressive states, including unipolar, bipolar, and mixed, with other adversities, including comorbid physical and psychological disorders, personality vulnerabilities, misuse of drugs and alcohol, and social and family problems. These issues are not always clearly differentiated from the depressive illness. Each of these adversities can worsen an existing mood disorder and influence the patient's resolve to persist with a treatment plan. Although this article is not focused strictly on treatment-resistant depression, these coexisting issues make depressive states harder to manage therapeutically. For brevity, the aim of this article has been limited to discussion of some complex situations that psychiatrists in general practice may encounter., Competing Interests: Dr. DePaulo serves as an unpaid consultant for Assurex Health, Inc. on behalf of the National Network of Depression Centers (NNDC), which is compensated for his consultation; he holds stock in CVS Health; he has a fiduciary but unpaid relationship with the NNDC as Chairperson of the Board of Directors, and he receives travel reimbursement from the NNDC (about $2,500 per year). The other authors report no financial relationships with commercial interests., (Copyright © 2020 by the American Psychiatric Association.)

Bipolar disorder is a highly heritable psychiatric disorder. We performed a genome-wide association study (GWAS) including 20,352 cases and 31,358 controls of European descent, with follow-up analysis of 822 variants with P < 1 × 10 -4 in an additional 9,412 cases and 137,760 controls. Eight of the 19 variants that were genome-wide significant (P < 5 × 10 -8 ) in the discovery GWAS were not genome-wide significant in the combined analysis, consistent with small effect sizes and limited power but also with genetic heterogeneity. In the combined analysis, 30 loci were genome-wide significant, including 20 newly identified loci. The significant loci contain genes encoding ion channels, neurotransmitter transporters and synaptic components. Pathway analysis revealed nine significantly enriched gene sets, including regulation of insulin secretion and endocannabinoid signaling. Bipolar I disorder is strongly genetically correlated with schizophrenia, driven by psychosis, whereas bipolar II disorder is more strongly correlated with major depressive disorder. These findings address key clinical questions and provide potential biological mechanisms for bipolar disorder.

Major depressive disorder (MDD) is a common illness accompanied by considerable morbidity, mortality, costs, and heightened risk of suicide. We conducted a genome-wide association meta-analysis based in 135,458 cases and 344,901 controls and identified 44 independent and significant loci. The genetic findings were associated with clinical features of major depression and implicated brain regions exhibiting anatomical differences in cases. Targets of antidepressant medications and genes involved in gene splicing were enriched for smaller association signal. We found important relationships of genetic risk for major depression with educational attainment, body mass, and schizophrenia: lower educational attainment and higher body mass were putatively causal, whereas major depression and schizophrenia reflected a partly shared biological etiology. All humans carry lesser or greater numbers of genetic risk factors for major depression. These findings help refine the basis of major depression and imply that a continuous measure of risk underlies the clinical phenotype.

Importance: Lithium is a first-line mood stabilizer for the treatment of bipolar affective disorder (BPAD). However, the efficacy of lithium varies widely, with a nonresponse rate of up to 30%. Biological response markers are lacking. Genetic factors are thought to mediate treatment response to lithium, and there is a previously reported genetic overlap between BPAD and schizophrenia (SCZ)., Objectives: To test whether a polygenic score for SCZ is associated with treatment response to lithium in BPAD and to explore the potential molecular underpinnings of this association., Design, Setting, and Participants: A total of 2586 patients with BPAD who had undergone lithium treatment were genotyped and assessed for long-term response to treatment between 2008 and 2013. Weighted SCZ polygenic scores were computed at different P value thresholds using summary statistics from an international multicenter genome-wide association study (GWAS) of 36 989 individuals with SCZ and genotype data from patients with BPAD from the Consortium on Lithium Genetics. For functional exploration, a cross-trait meta-GWAS and pathway analysis was performed, combining GWAS summary statistics on SCZ and response to treatment with lithium. Data analysis was performed from September 2016 to February 2017., Main Outcomes and Measures: Treatment response to lithium was defined on both the categorical and continuous scales using the Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder score. The effect measures include odds ratios and the proportion of variance explained., Results: Of the 2586 patients in the study (mean [SD] age, 47.2 [13.9] years), 1478 were women and 1108 were men. The polygenic score for SCZ was inversely associated with lithium treatment response in the categorical outcome, at a threshold P < 5 × 10-2. Patients with BPAD who had a low polygenic load for SCZ responded better to lithium, with odds ratios for lithium response ranging from 3.46 (95% CI, 1.42-8.41) at the first decile to 2.03 (95% CI, 0.86-4.81) at the ninth decile, compared with the patients in the 10th decile of SCZ risk. In the cross-trait meta-GWAS, 15 genetic loci that may have overlapping effects on lithium treatment response and susceptibility to SCZ were identified. Functional pathway and network analysis of these loci point to the HLA antigen complex and inflammatory cytokines., Conclusions and Relevance: This study provides evidence for a negative association between high genetic loading for SCZ and poor response to lithium in patients with BPAD. These results suggest the potential for translational research aimed at personalized prescribing of lithium.

Bipolar disorder (BD) is a genetically complex mental illness characterized by severe oscillations of mood and behaviour. Genome-wide association studies (GWAS) have identified several risk loci that together account for a small portion of the heritability. To identify additional risk loci, we performed a two-stage meta-analysis of >9 million genetic variants in 9,784 bipolar disorder patients and 30,471 controls, the largest GWAS of BD to date. In this study, to increase power we used ∼2,000 lithium-treated cases with a long-term diagnosis of BD from the Consortium on Lithium Genetics, excess controls, and analytic methods optimized for markers on the X-chromosome. In addition to four known loci, results revealed genome-wide significant associations at two novel loci: an intergenic region on 9p21.3 (rs12553324, P =  5.87 × 10  -   9 ; odds ratio (OR) = 1.12) and markers within ERBB2 (rs2517959, P =  4.53 × 10  -   9 ; OR = 1.13). No significant X-chromosome associations were detected and X-linked markers explained very little BD heritability. The results add to a growing list of common autosomal variants involved in BD and illustrate the power of comparing well-characterized cases to an excess of controls in GWAS., (Published by Oxford University Press 2016. This work is written by US Government employees and is in the public domain in the United States.)

Background: Lithium is a first-line treatment in bipolar disorder, but individual response is variable. Previous studies have suggested that lithium response is a heritable trait. However, no genetic markers of treatment response have been reproducibly identified., Methods: Here, we report the results of a genome-wide association study of lithium response in 2563 patients collected by 22 participating sites from the International Consortium on Lithium Genetics (ConLiGen). Data from common single nucleotide polymorphisms (SNPs) were tested for association with categorical and continuous ratings of lithium response. Lithium response was measured using a well established scale (Alda scale). Genotyped SNPs were used to generate data at more than 6 million sites, using standard genomic imputation methods. Traits were regressed against genotype dosage. Results were combined across two batches by meta-analysis., Findings: A single locus of four linked SNPs on chromosome 21 met genome-wide significance criteria for association with lithium response (rs79663003, p=1·37 × 10(-8); rs78015114, p=1·31 × 10(-8); rs74795342, p=3·31 × 10(-9); and rs75222709, p=3·50 × 10(-9)). In an independent, prospective study of 73 patients treated with lithium monotherapy for a period of up to 2 years, carriers of the response-associated alleles had a significantly lower rate of relapse than carriers of the alternate alleles (p=0·03268, hazard ratio 3·8, 95% CI 1·1-13·0)., Interpretation: The response-associated region contains two genes for long, non-coding RNAs (lncRNAs), AL157359.3 and AL157359.4. LncRNAs are increasingly appreciated as important regulators of gene expression, particularly in the CNS. Confirmed biomarkers of lithium response would constitute an important step forward in the clinical management of bipolar disorder. Further studies are needed to establish the biological context and potential clinical utility of these findings., Funding: Deutsche Forschungsgemeinschaft, National Institute of Mental Health Intramural Research Program., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Genome-wide association studies (GWAS) have implicated ANK3 as a susceptibility gene for bipolar disorder (BP). We examined whether epistasis with ANK3 may contribute to the "missing heritability" in BP. We first identified via the STRING database 14 genes encoding proteins with prior biological evidence that they interact molecularly with ANK3. We then tested for statistical evidence of interactions between SNPs in these genes in association with BP in a discovery GWAS dataset and two replication GWAS datasets. The most significant interaction in the discovery GWAS was between SNPs in ANK3 and KCNQ2 (p = 3.18 × 10(-8)). A total of 31 pair-wise interactions involving combinations between two SNPs from KCNQ2 and 16 different SNPs in ANK3 were significant after permutation. Of these, 28 pair-wise interactions were significant in the first replication GWAS. None were significant in the second replication GWAS, but the two SNPs from KCNQ2 were found to significantly interact with five other SNPs in ANK3, suggesting possible allelic heterogeneity. KCNQ2 forms homo- and hetero-meric complexes with KCNQ3 that constitute voltage-gated potassium channels in neurons. ANK3 is an adaptor protein that, through its interaction with KCNQ2 and KCNQ3, directs the localization of this channel in the axon initial segment (AIS). At the AIS, the KCNQ2/3 complex gives rise to the M-current, which stabilizes the neuronal resting potential and inhibits repetitive firing of action potentials. Thus, these channels act as "dampening" components and prevent neuronal hyperactivity. The interactions between ANK3 and KCNQ2 merit further investigation, and if confirmed, may motivate a new line of research into a novel therapeutic target for BP.

Genome-wide association studies (GWAS) have identified several susceptibility loci for bipolar disorder (BP), most notably ANK3. However, most of the inherited risk for BP remains unexplained. One reason for the limited success may be the genetic heterogeneity of BP. Clinical sub-phenotypes of BP may identify more etiologically homogeneous subsets of patients, which can be studied with increased power to detect genetic variation. Here, we report on a mega-analysis of two widely studied sub-phenotypes of BP, age at onset and psychotic symptoms, which are familial and clinically significant. We combined data from three GWAS: NIMH Bipolar Disorder Genetic Association Information Network (GAIN-BP), NIMH Bipolar Disorder Genome Study (BiGS), and a German sample. The combined sample consisted of 2,836 BP cases with information on sub-phenotypes and 2,744 controls. Imputation was performed, resulting in 2.3 million SNPs available for analysis. No SNP reached genome-wide significance for either sub-phenotype. In addition, no SNP reached genome-wide significance in a meta-analysis with an independent replication sample. We had 80% power to detect associations with a common SNP at an OR of 1.6 for psychotic symptoms and a mean difference of 1.8 years in age at onset. Age at onset and psychotic symptoms in BP may be influenced by many genes of smaller effect sizes or other variants not measured well by SNP arrays, such as rare alleles., (Copyright © 2011 Wiley-Liss, Inc.)

In an effort to decrease the suicide rate in adolescents, many interventions have focused on school-based suicide prevention programs. Alternatively, depression education in schools might be effective in decreasing the morbidity, mortality, and stigma associated with adolescent depression. The Adolescent Depression Awareness Program (ADAP) developed a 3-hour curriculum to teach high school students about the illness of depression. The purpose of this study was to assess the effectiveness of the ADAP curriculum in improving high school students' knowledge about depression. From 2001 to 2005, 3,538 students were surveyed on their knowledge about depression before and after exposure to the ADAP curriculum. The number of students scoring 80% or higher on the assessment tool more than tripled from pretest to posttest (701 to 2,180), suggesting the effectiveness of the ADAP curriculum. Further study and replication are required to determine if improved knowledge translates into increased treatment-seeking behavior.

Objective: Family studies have suggested that postpartum mood symptoms might have a partly genetic etiology. The authors used a genome-wide linkage analysis to search for chromosomal regions that harbor genetic variants conferring susceptibility for such symptoms. The authors then fine-mapped their best linkage regions, assessing single nucleotide polymorphisms (SNPs) for genetic association with postpartum symptoms., Method: Subjects were ascertained from two studies: the NIMH Genetics Initiative Bipolar Disorder project and the Genetics of Recurrent Early-Onset Depression. Subjects included women with a history of pregnancy, any mood disorder, and information about postpartum symptoms. In the linkage study, 1,210 women met criteria (23% with postpartum symptoms), and 417 microsatellite markers were analyzed in multipoint allele sharing analyses. For the association study, 759 women met criteria (25% with postpartum symptoms), and 16,916 SNPs in the regions of the best linkage peaks were assessed for association with postpartum symptoms., Results: The maximum linkage peak for postpartum symptoms occurred on chromosome 1q21.3-q32.1, with a chromosome-wide significant likelihood ratio Z score (Z(LR)) of 2.93 (permutation p=0.02). This was a significant increase over the baseline Z(LR) of 0.32 observed at this locus among all women with a mood disorder (permutation p=0.004). Suggestive linkage was also found on 9p24.3-p22.3 (Z(LR)=2.91). In the fine-mapping study, the strongest implicated gene was HMCN1 (nominal p=0.00017), containing four estrogen receptor binding sites, although this was not region-wide significant., Conclusions: This is the first study to examine the genetic etiology of postpartum mood symptoms using genome-wide data. The results suggest that genetic variations on chromosomes 1q21.3-q32.1 and 9p24.3-p22.3 may increase susceptibility to postpartum mood symptoms.

We sought to determine whether premenstrual mood symptoms exhibit familial aggregation in bipolar disorder or major depression pedigrees. Two thousand eight hundred seventy-six women were interviewed with the Diagnostic Interview for Genetic Studies as part of either the NIMH Genetics Initiative Bipolar Disorder Collaborative study or the Genetics of Early Onset Major Depression (GenRED) study and asked whether they had experienced severe mood symptoms premenstrually. In families with two or more female siblings with bipolar disorder (BP) or major depressive disorder (MDD), we examined the odds of having premenstrual mood symptoms given one or more siblings with these symptoms. For the GenRED MDD sample we also assessed the impact of personality as measured by the NEO-FFI. Premenstrual mood symptoms did not exhibit familial aggregation in families with BP or MDD. We unexpectedly found an association between high NEO openness scores and premenstrual mood symptoms, but neither this factor, nor NEO neuroticism influenced evidence for familial aggregation of symptoms. Limitations include the retrospective interview, the lack of data on premenstrual dysphoric disorder, and the inability to control for factors such as medication use.

Context: The Wnt signaling pathways promote cell growth and are best known for their role in embryogenesis and cancer. Several lines of evidence suggest that these pathways might also be involved in bipolar disorder., Objective: To test for an association between candidate genes in the Wnt signaling pathways and disease susceptibility in a family-based bipolar disorder study., Design: Two hundred twenty-seven tagging single- nucleotide polymorphisms (SNPs) from 34 genes were successfully genotyped. Initial results led us to focus on the gene PPARD, in which we genotyped an additional 13 SNPs for follow-up., Setting: Nine academic medical centers in the United States., Participants: Five hundred fifty-four offspring with bipolar disorder and their parents from 317 families., Main Outcome Measures: Family-based association using FBAT and HBAT (http://www.biostat.harvard.edu/~fbat/default.html; Harvard School of Public Health, Boston, Massachusetts). Exploratory analyses testing for interactions of PPARD SNPs with clinical covariates and with other Wnt genes were conducted with GENASSOC (Stata Corp, College Station, Texas)., Results: In the initial analysis, the most significantly associated SNP was rs2267665 in PPARD (nominal P < .001). This remained significant at P = .05 by permutation after accounting for all SNPs tested. Additional genotyping in PPARD yielded 4 SNPs in 1 haplotype block that were significantly associated with bipolar disorder (P < .01), the most significant being rs9462082 (P < .001). Exploratory analyses revealed significant evidence (P < .01) for interactions of rs9462082 with poor functioning on the Global Assessment Scale (odds ratio [OR], 3.36; 95% confidence interval [CI], 1.85-6.08) and with SNPs in WNT2B (rs3790606: OR, 2.56; 95% CI, 1.67-4.00) and WNT7A (rs4685048: OR, 1.79; 95% CI, 1.23-2.63)., Conclusions: We found evidence for association of bipolar disorder with PPARD, a gene in the Wnt signaling pathway. The consistency of this result with one from the Wellcome Trust Case-Control Consortium encourages further study. If the finding can be confirmed in additional samples, it may illuminate a new avenue for understanding the pathogenesis of severe bipolar disorder and developing more effective treatments.

Objective: Rapid switching of moods in bipolar disorder has been associated with early age at onset, panic comorbidity, and suicidality. This study aims to confirm these associations and investigate other potential correlates of rapid switching of mood using families from a multisite bipolar linkage study., Methods: The subjects were comprised of 1,143 probands and relatives with diagnosis of bipolar disorder. All subjects were interviewed directly with a standard diagnostic instrument, and all subjects who met criteria for bipolar disorder were asked if their moods had ever switched rapidly., Results: Individuals with rapid mood switching had significantly earlier age at onset (18 versus 21 years, p < 0.00001), higher comorbid anxiety (47% versus 26%, p < 0.00001) and substance use disorders (52% versus 42%, p = 0.0006), higher rate of violent behavior (6% versus 3%, p < 0.004), suicidal behavior (46% versus 31%, p < 0.00001), and nonsuicidal self-harm (13% versus 6%, p < 0.0002). Multiple logistic regression analysis found significant net effects on rapid mood switching for early emergence of symptoms [odds ratio (OR) = 0.62; 95% confidence interval (CI): 0.45-0.85]; anxiety comorbidity (OR = 2.31; 95% CI: 1.34-3.98); and hypersensitivity to antidepressants (OR = 2.05; 95% CI: 1.49-2.83) as the strongest predictors., Conclusions: This confirms earlier reports associating rapid switching with a more complex clinical course, in particular early emergence of bipolar symptomatology, antidepressant activation, and anxiety comorbidity. These results support a clinical differentiation of bipolar disorder into subtypes based on symptom stability.

Objective: We describe the etiology of clinical forms of depression and their interaction with workplace factors., Methods: We performed selective literature searches in pertinent research areas and reviewed the literature in the context of clinical experience in several depression programs at Johns Hopkins., Results: Substantial research exists about the causes of depression. The causes of clinical forms of depression are complex. Genetic factors, several specific brain disorders, gender, as well as life events or circumstances all are involved in the causal pathway. Research addressing how the work environment impacts depression and its role in aggravating or alleviating depression is more limited., Conclusions: Research findings about the various causal connections in depressive disorders may provide some guides to treatment as well as to further research on depression in the workplace.

Objectives: We sought to determine if postpartum mood symptoms and depressive episodes exhibit familial aggregation in bipolar I pedigrees., Methods: A total of 1,130 women were interviewed with the Diagnostic Interview for Genetic Studies as part of the National Institute of Mental Health (NIMH) Genetics Initiative Bipolar Disorder Collaborative Study and were asked whether they had ever experienced mood symptoms within four weeks postpartum. Women were also asked whether either of two major depressive episodes described in detail occurred postpartum. We examined the odds of postpartum mood symptoms in female siblings, who had previously been pregnant and had a diagnosis of bipolar I, bipolar II, or schizoaffective (bipolar type) disorders (n = 303), given one or more relatives with postpartum mood symptoms., Results: The odds ratio for familial aggregation of postpartum mood symptoms was 2.31 (p = 0.011) in an Any Mood Symptoms analysis (n = 304) and increased to 2.71 (p = 0.005) when manic symptoms were excluded, though this was not significantly different from the Any Mood Symptoms analysis. We also examined familial aggregation of postpartum major depressive episodes; however, the number of subjects was small., Conclusions: Limitations of the study include the retrospective interview, the fact that the data were collected for other purposes and the inability to control for such factors as medication use. Taken together with previous studies, these data provide support for the hypothesis that there may be a genetic basis for the trait of postpartum mood symptoms generally and postpartum depressive symptoms in particular in women with bipolar disorder. Genetic linkage and association studies incorporating this trait are warranted.

Objective: Bipolar disorder (BD) II is characterized by recurrent hypomanic and depressive episodes and has been somewhat of a controversial diagnosis since its description in the 1970s. Clinical opinions notwithstanding, the biological validity of BD II was supported in a genetic study of 58 multiplex bipolar families wherein the statistical evidence for linkage derived from BD II sibling-pairs sharing marker alleles on chromosome 18q. The BD II phenotype alone has never been studied in a genome-wide scan analysis in the current or other bipolar family samples. We have performed genome-wide non-parametric analysis on 74 bipolar pedigrees using only the BD II phenotype as affection model., Methods: This sample consists of the 65 pedigrees previously reported and 9 additional novel pedigrees that had BD II exclusively, as the affected phenotype. In the entire sample, there were 146 all possible relative-pairs. Analysis was performed using the non-parametric method in GENEHUNTER, with the 'ALL' option that computes linkage scores in all individuals in a pedigree simultaneously., Results: The current analyses supported the previous finding on chromosome 18q21. In addition a peak with a non-parametric LOD (NPL) of 2.07 occurred between D9S915 and D9S2157, located on 9q34. Analysis of the nine BD II families alone identified peaks on 9p13 and 9q33, with NPL scores of 3.20 and 2.09, respectively. There was no evidence at 18q21 in these nine families., Conclusions: This suggests that there may be substantial differences in the etiology of BD in families that have BD II exclusively as the diagnosis.

Objective: The purpose of this study is to test for heterogeneity in bipolar families based on the differential parental transmission of disease., Methods: Complex segregation analyses of 260 bipolar families, ascertained by the Johns Hopkins Bipolar Disorder Study, was performed based on the evidence for a parent-of-origin effect in the inheritance pattern by using REGD in Statistical Analysis for Genetic Epidemiology, Release 3.1 program., Results: A Mendelian dominant model provided the best explanation in 57 paternal pedigrees (pedigrees with an affected paternal lineage). No evidence of Mendelian inheritance existed among 141 pedigrees showing maternal transmission. A likelihood ratio test for heterogeneity on the basis of best-fitting Mendelian dominant model showed significant differences between these two groups., Conclusion: These results suggest that pedigrees with no evidence of maternal transmission of bipolar disorder may represent a unique genetic subgroup of multiplex bipolar families.

Objective: Mood-incongruent psychotic features in bipolar disorder may signify a more severe form of the illness and might represent phenotypic manifestations of susceptibility genes shared with schizophrenia. This study attempts to characterize clinical correlates, familial aggregation, and genetic linkage in subjects with these features., Method: Subjects were drawn from The National Institute of Mental Health (NIMH) Genetics Initiative Bipolar Disorder Collaborative cohort, consisting of 708 families recruited at 10 academic medical centers. Subjects with mood-incongruent and mood-congruent psychotic features were compared on clinical variables. Familial aggregation was tested using a proband-predictive model and generalized estimating equations. A genome-wide linkage scan incorporating a mood-incongruence covariate was performed., Results: Mood-incongruent psychotic features were associated with an increased rate of hospitalization and attempted suicide. A proband with mood-incongruence predicted mood-incongruence in relatives with bipolar I disorder when compared with all other subjects and when compared with subjects with mood-congruent psychosis. The presence of mood-incongruent psychotic features increased evidence for linkage on chromosomes 13q21-33 and 2p11-q14. These logarithm of the odds ratio (LOD) scores and their increase from baseline met empirical genome-wide suggestive criteria for significance., Conclusions: Mood-incongruent psychotic features showed evidence of a more severe course, familial aggregation, and suggestive linkage to two chromosomal regions previously implicated in major mental illness susceptibility. The 13q21-33 finding supports prior evidence of bipolar disorder/schizophrenia overlap in this region, while the 2p11-q14 finding is, to the authors' knowledge, the first to suggest that this schizophrenia linkage region might also harbor a bipolar disorder susceptibility gene.

Objective: The authors studied a dense map of single nucleotide polymorphism (SNP) DNA markers on chromosome 15q25-q26 to maximize the informativeness of genetic linkage analyses in a region where they previously reported suggestive evidence for linkage of recurrent early-onset major depressive disorder., Method: In 631 European-ancestry families with multiple cases of recurrent early-onset major depressive disorder, 88 SNPs were genotyped, and multipoint allele-sharing linkage analyses were carried out. Marker-marker linkage disequilibrium was minimized, and a simulation study with founder haplotypes from these families suggested that linkage scores were not inflated by linkage disequilibrium., Results: The dense SNP map increased the information content of the analysis from around 0.7 to over 0.9. The maximum evidence for linkage was the Z likelihood ratio score statistic of Kong and Cox (Z(LR))=4.69 at 109.8 cM. The exact p value was below the genomewide significance threshold. By contrast, in the genome scan with microsatellite markers at 9 cM spacing, the maximum Z(LR) for European-ancestry families was 3.43 (106.53 cM). It was estimated that the linked locus or loci in this region might account for a 20% or less populationwide increase in risk to siblings of cases., Conclusions: This region has produced modestly positive evidence for linkage to depression and related traits in other studies. These results suggest that DNA sequence variations in one or more genes in the 15q25-q26 region can increase susceptibility to major depression and that efforts are warranted to identify these genes.

Objective: The authors carried out a genomewide linkage scan to identify chromosomal regions likely to contain genes that contribute to susceptibility to recurrent early-onset major depressive disorder, the form of the disorder with the greatest reported risk to relatives of index cases., Method: Microsatellite DNA markers were studied in 656 families with two or more such cases (onset before age 31 in probands and age 41 in other relatives), including 1,494 informative "all possible" affected relative pairs (there were 894 independent affected sibling pairs). Analyses included a primary multipoint allele-sharing analysis (with ALLEGRO) and a secondary logistic regression analysis taking the sex of each relative pair into account (male-male, male-female, female-female)., Results: Genomewide suggestive evidence for linkage was observed on chromosome 15q25-q26 (at 105.4 centimorgans [cM]). The authors previously reported genomewide significant linkage in this region in the first 297 families. In the secondary analysis, after empirical genomewide correction for multiple testing, suggestive linkage results were observed on chromosome 17p12 (28.0 cM, excess sharing in male-male and male-female pairs) and on chromosome 8p22-p21.3 (25.1 cM, excess sharing in male-male pairs)., Conclusions: These regions of chromosomes 15q, 17p, and 8p might contain genes that contribute to susceptibility to major depression and related disorders. Evidence for linkage has been reported independently in the same regions of chromosome 15q for major depression and of chromosome 8p for related personality traits.

Previous evidence suggests that the inheritance of bipolar disorder (BP) may vary depending on the age at onset (AAO). Therefore, we sought to incorporate AAO as a covariate in linkage analyses of BP using two different methods, LODPAL and ordered-subset analysis (OSA), in genomewide scans of 150 multiplex pedigrees with 874 individuals. The LODPAL analysis identified two loci, on chromosomes 21q22.13 (LOD = 3.29; empirical chromosomewide P value = .009) and 18p11.2 (LOD = 2.83; empirical chromosomewide P = .05), with increased linkage among subjects who had early onset (AAO < or = 21 years) and later onset (AAO >21 years), respectively. The finding on 21q22.13 was significant at the chromosomewide level, even after correction for multiple testing. Moreover, a similar finding was observed in an independent sample of 65 pedigrees (LOD = 2.88; empirical chromosomewide P = .025). The finding on 18p11.2 was only nominally significant and was not observed in the independent sample. However, 18p11.2 emerged as one of the strongest regions in the OSA (LOD = 2.92; empirical P = .001), in which it was the only finding to meet chromosomewide levels of significance after correction for multiple testing. These results suggest that 21q22.13 and 18p11.2 may harbor genes that increase the risks for early-onset and later-onset forms of BP, respectively. There have been previous reports of linkage on 21q22.13 and 18p11.2, but the findings have not been consistent. This inconsistency may be due to differences in the AAO characteristics of the samples examined. Future studies to fine map susceptibility genes for BP on chromosomes 21q22.13 and 18p11.2 should take AAO into account.

Background: We have reported genetic linkage between bipolar disorder and markers on chromosome 6q16.3-22.1 in the National Institute of Mental Health Genetics Initiative wave 3 pedigrees. Here we test for: 1) robustness of the linkage to differing analysis methods, genotyping error, and gender-specific maps; 2) parent-of-origin effects; and 3) interaction with markers within the schizophrenia linkage region on chromosome 6p., Methods: Members of 245 families ascertained through a sibling pair affected with bipolar I or schizoaffective-bipolar disorder were genotyped with 18 markers spanning chromosome 6. Nonparametric linkage analysis was performed., Results: Linkage to 6q is robust to analysis method, gender-specific map differences, and genotyping error. The locus confers a 1.4-fold increased risk. Affected siblings share the maternal more often than the paternal chromosome (p =.006), which could reflect a maternal parent-of-origin effect. There is a positive correlation between family-specific linkage scores on 6q and those on 6p22.2 (r =.26; p <.0001). Linkage analysis for each locus conditioned on evidence of linkage to the other increases the evidence for linkage at both loci (p <.0005). Logarithm of the odds (LOD) scores increased from 2.26 to 5.42 on 6q and from.35 to 2.26 on 6p22.2., Conclusions: These results support linkage of bipolar disorder to 6q, uncover a maternal parent-of-origin effect, and demonstrate an interaction of this locus with one on chromosome 6p22.2, previously linked only to schizophrenia.

A genome scan was performed on the first phase sample of the Genetics of Recurrent Early-Onset Depression (GenRED) project. The sample consisted of 297 informative families containing 415 independent affected sibling pairs (ASPs), or, counting all possible pairs, 685 informative affected relative pairs (555 ASPs and 130 other pair types). Affected cases had recurrent major depressive disorder (MDD) with onset before age 31 years for probands or age 41 years for other affected relatives; the mean age at onset was 18.5 years, and the mean number of depressive episodes was 7.3. The Center for Inherited Disease Research genotyped 389 microsatellite markers (mean spacing of 9.3 cM). The primary linkage analysis considered allele sharing in all possible affected relative pairs with the use of the Z(lr) statistic computed by the ALLEGRO program. A secondary logistic regression analysis considered the effect of the sex of the pair as a covariate. Genomewide significant linkage was observed on chromosome 15q25.3-26.2 (Zlr=4.14, equivalent LOD = 3.73, empirical genomewide P=.023). The linkage was not sex specific. No other suggestive or significant results were observed in the primary analysis. The secondary analysis produced three regions of suggestive linkage, but these results should be interpreted cautiously because they depended primarily on the small subsample of 42 male-male pairs. Chromosome 15q25.3-26.2 deserves further study as a candidate region for susceptibility to MDD.

Background: In 1989 the National Institute of Mental Health began a collaborative effort to identify genes for bipolar disorder. The first 97 pedigrees showed evidence of linkage to chromosomes 1, 6, 7, 10, 16, and 22 (Nurnberger et al 1997). An additional 56 bipolar families have been genotyped, and the combined sample of 153 pedigrees studied., Methods: Three hierarchical affection status models were analyzed with 513 simple sequence repeat markers; 298 were common across all pedigrees. The primary analysis was a nonparametric genome-wide scan. We performed conditional analyses based on epistasis or heterogeneity for five regions., Results: One region, on 16p13, was significant at the genome-wide p <.05 level. Four additional chromosomal regions (20p12, 11p15, 6q24, and 10p12) showed nominally significant linkage findings (p

Background: Heterogeneity within the diagnostic construct of bipolar disorder is most likely an obstacle to discovering its causes. Phenomena in the bipolar spectrum, including rapid cycling, cyclothymia, and affective instability of borderline personality, may be important markers of etiologic heterogeneity. Rapid switching of mood may be central to these phenomena., Methods: We performed a case-control study, using diagnostic data from a multisite bipolar disorder linkage study, to explore clinical and demographic factors potentially related to rapid switching in bipolar disorder. Participants were 18 years or older and members of a family in which 2 or more first-degree relatives had bipolar disorder. Of 718 individuals interviewed and diagnosed as having bipolar disorder, 603 gave sufficient information about rapid switching and thus constituted the study group (60% female; mean age, 41 years; and mean education level, 13.8 years)., Results: Rapid switching of mood was reported by 44% of interviewees and was associated with early age at onset of bipolar disorder, higher risk of anxiety and substance abuse or dependence comorbidity, suicide attempts, antidepressant drug use, and having a relative with rapid switching., Conclusions: Rapid switching is associated with a complex clinical course of bipolar disorder. These results extend previous associations among rapid switching, anxiety, substance abuse, and early onset of bipolar disorder to a family study population. Rapid switching of mood seems to be the core phenomenon behind several variants of non-DSM-IV rapid cycling, DSM-III-R mixed states, and borderline personality disorder and the link connecting comorbidity, suicide, and early onset of bipolar disorder. Further biological investigation of the rapid-switching phenomenon is justified on epidemiologic grounds.

Background: We recently reported evidence of linkage of bipolar disorder to chromosome 18q, with a paternal logarithm of odds (LOD) score of 4.67 (p =.004) in a clinically defined subset of families. Like other linkage studies, we had to rely on imprecise genetic maps to establish the marker order. Here, we test for linkage in the same sample with a denser set of markers, now physically ordered according to the draft sequence of the human genome., Methods: Families were ascertained through probands with bipolar I disorder and diagnosed with reliable methods. Genotypes were generated for 12 microsatellite markers within an 11-centimorgan (cM) region of chromosome 18q22. Multipoint affected sib-pair linkage analysis was performed in a set of 16 nuclear families., Results: The additional markers significantly increased the total genetic information extracted from our sample. We also observed an increase in the LOD score (to 5.42, p =.0066) and linkage resolution. The approximate 1-LOD support interval is now 9 male cM., Conclusions: The results strengthen our previous findings and further define a region suitable for genetic fine-mapping analysis on chromosome 18q. Our data suggest that a dense set of markers, when physically ordered, can increase the informational value of genetic linkage signals.