GENOME-WIDE ASSOCIATION STUDY (GWAS) AND GENOME-WIDE BY ENVIRONMENT INTERACTION STUDY (GWEIS) OF DEPRESSIVE SYMPTOMS IN AFRICAN AMERICAN AND HISPANIC/LATINA WOMEN.

BACKGROUND: Genome-wide association studies (GWAS) have made little progress in identifying variants linked to depression. We hypothesized that examining depressive symptoms and considering gene-environment interaction (GxE) might improve efficiency for gene discovery. We therefore conducted a GWAS and genome-wide by environment interaction study (GWEIS) of depressive symptoms. METHODS: Using data from the SHARe cohort of the Women's Health Initiative, comprising African Americans (n = 7,179) and Hispanics/Latinas (n = 3,138), we examined genetic main effects and GxE with stressful life events and social support. We also conducted a heritability analysis using genome-wide complex trait analysis (GCTA). Replication was attempted in four independent cohorts. RESULTS: No SNPs achieved genome-wide significance for main effects in either discovery sample. The top signals in African Americans were rs73531535 (located 20 kb from GPR139, P = 5.75 × 10(-8) ) and rs75407252 (intronic to CACNA2D3, P = 6.99 × 10(-7) ). In Hispanics/Latinas, the top signals were rs2532087 (located 27 kb from CD38, P = 2.44 × 10(-7) ) and rs4542757 (intronic to DCC, P = 7.31 × 10(-7) ). In the GEWIS with stressful life events, one interaction signal was genome-wide significant in African Americans (rs4652467; P = 4.10 × 10(-10) ; located 14 kb from CEP350). This interaction was not observed in a smaller replication cohort. Although heritability estimates for depressive symptoms and stressful life events were each less than 10%, they were strongly genetically correlated (rG = 0.95), suggesting that common variation underlying self-reported depressive symptoms and stressful life event exposure, though modest on their own, were highly overlapping in this sample. CONCLUSIONS: Our results underscore the need for larger samples, more GEWIS, and greater investigation into genetic and environmental determinants of depressive symptoms in minorities.

Bipolar polygenic loading and bipolar spectrum features in major depressive disorder.

OBJECTIVES: Family and genetic studies indicate overlapping liability for major depressive disorder and bipolar disorder. The purpose of the present study was to determine whether this shared genetic liability influences clinical presentation. METHODS: A polygenic risk score for bipolar disorder, derived from a large genome-wide association meta-analysis, was generated for each subject of European-American ancestry (n = 1,274) in the Sequential Treatment Alternatives to Relieve Depression study (STAR*D) outpatient major depressive disorder cohort. A hypothesis-driven approach was used to test for association between bipolar disorder risk score and features of depression associated with bipolar disorder in the literature. Follow-up analyses were performed in two additional cohorts. RESULTS: A generalized linear mixed model including seven features hypothesized to be associated with bipolar spectrum illness was significantly associated with bipolar polygenic risk score [F = 2.07, degrees of freedom (df) = 7, p = 0.04]. Features included early onset, suicide attempt, recurrent depression, atypical depression, subclinical mania, subclinical psychosis, and severity. Post-hoc univariate analyses demonstrated that the major contributors to this omnibus association were onset of illness at age ≤ 18 years [odds ratio (OR) = 1.2, p = 0.003], history of suicide attempt (OR = 1.21, p = 0.03), and presence of at least one manic symptom (OR = 1.16, p = 0.02). The maximal variance in these traits explained by polygenic score ranged from 0.8% to 1.1%. However, analyses in two replication cohorts testing a five-feature model did not support this association. CONCLUSIONS: Bipolar genetic loading appeared to be associated with bipolar-like presentation in major depressive disorder in the primary analysis. However, the results were at most inconclusive because of lack of replication. Replication efforts were challenged by different ascertainment and assessment strategies in the different cohorts. The methodological approach described here may prove useful in applying genetic data to clarify psychiatric nosology in future studies.

A variant associated with nicotine dependence, lung cancer and peripheral arterial disease.

Smoking is a leading cause of preventable death, causing about 5 million premature deaths worldwide each year. Evidence for genetic influence on smoking behaviour and nicotine dependence (ND) has prompted a search for susceptibility genes. Furthermore, assessing the impact of sequence variants on smoking-related diseases is important to public health. Smoking is the major risk factor for lung cancer (LC) and is one of the main risk factors for peripheral arterial disease (PAD). Here we identify a common variant in the nicotinic acetylcholine receptor gene cluster on chromosome 15q24 with an effect on smoking quantity, ND and the risk of two smoking-related diseases in populations of European descent. The variant has an effect on the number of cigarettes smoked per day in our sample of smokers. The same variant was associated with ND in a previous genome-wide association study that used low-quantity smokers as controls, and with a similar approach we observe a highly significant association with ND. A comparison of cases of LC and PAD with population controls each showed that the variant confers risk of LC and PAD. The findings provide a case study of a gene-environment interaction, highlighting the role of nicotine addiction in the pathology of other serious diseases.

Association between child psychiatric emergency room outcomes and dimensions of psychopathology.

OBJECTIVE: To determine the degree to which dimensional psychopathology predicts length of stay in an emergency department (ED) and need for hospital admission among children with psychiatric complaints. METHOD: Electronic health records of children age 4-17 years who presented to the ED of a large academic medical center were analyzed using a natural language processing tool to estimate Research Domain Criteria (RDoC) symptom scores. These scores' association with length of stay and probability of admission versus discharge to home were evaluated. RESULTS: We identified 3061 children and adolescents who presented to the ED and were evaluated by the psychiatry service between November 2008 and March 2015. Median length of stay was 7.8 h (interquartile range 5.2-14.3 h) and 1696 (55.4%) were admitted to the hospital. Higher estimated RDoC arousal, cognitive, positive, and social domain scores were associated with increased length of stay in multiple regression models, adjusted for age, sex, race, private insurance, voluntary admission, and diagnostic categories. In similarly adjusted models, odds of hospital admission were increased by higher RDoC arousal and cognitive domain scores and decreased by higher negative domain scores. CONCLUSIONS: A natural language processing tool to characterize dimensional psychopathology identified features associated with differential outcomes in children in the psychiatric ED, most notably symptoms reflecting arousal and cognitive function. Methodologically, this in silico approach to risk stratification should facilitate precision psychiatry in children within the emergency setting.

Norepinephrine and serotonin imbalance in the locus coeruleus in bipolar disorder.

OBJECTIVES: Abnormalities in norepinephrine (NE) and serotonin (5-HT) are implicated in bipolar disorder (BD). We examined 5-HT input and NE neurons in the locus coeruleus (LC, the NE nucleus that innervates the forebrain) in BD by quantifying immunoreactivity (IR) for tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), the biosynthetic enzymes for NE and 5-HT, respectively. METHODS: Six suicides with BD were compared to matched normal controls and unipolar major depression suicides, using immunocytochemistry with computer-assisted quantification of immunoreactivity. RESULTS: Depressed bipolar suicides had 26.7 +/- 1.3% of LC area occupied by the TH immunoreactive (TH-IR) process, while controls had 50.7 +/- 8% (p = 0.002) and unipolar depressed suicides had 50.3 +/- 2.5% (p = 0.003). In bipolars, these processes did not stain as darkly (1.9 +/- 0.5 x background) as controls (2.9 +/- 0.9 x background; p = 0.01) or unipolars (2.9 +/- 0.6 x background; p = 0.002). Bipolar suicides also had less TPH-IR processes in the LC (11.7 +/- 10%) compared with controls (32.8 +/- 8.8%; p = 0.01) or unipolar suicides (30.3 +/- 8%; p = 0.02). The TPH-IR intensity did not differ between groups. CONCLUSIONS: We found less TH-IR and TPH-IR in the LC in depressed bipolar suicides, but not unipolar suicides, suggesting that both NE and 5-HT activity is lower in BD. Studies during manic or euthymic states will determine whether these changes are mood state dependent.

Plasma S-100B protein in Chinese patients with schizophrenia: comparison with healthy controls and effect of antipsychotics treatment.

PURPOSE: To examine the possibility that structural damage to the brain may play a role in the pathogenesis of schizophrenia by measuring the level of plasma S-100B, a calcium-binding protein found predominantly in the cytosol of glial cells. METHOD: Fifty-seven Chinese psychiatric inpatients who met DSM-IV diagnosis of schizophrenia and 60 healthy controls were enrolled in the study. Patients were assessed with the Positive and Negative Symptoms Scale (PANSS) at admission and at 12 weeks after treatment. Plasma samples were collected from patients and controls and S-100B protein was assayed using ELISA. RESULTS: (1) 29 of 57 patients (50.9%) showed increased S-100B level compared to the mean level of 60 healthy controls (p<0.005) vs. only 1 of 60 (1.67%) controls. The S-100B levels of unmedicated (0.119+/-0.059microg/L) and medicated patients (0.117+/-.0.057microg/L) were significantly higher than controls (0.067+/-0.022microg/L, both p<0.001), and S-100B levels of unmedicated patients were higher than those of medicated patients (p=0.024); (2) at admission, S-100B level was positively correlated with total score of PANSS (r=0.269, p=0.043), especially with negative subscore of PANSS (r=0.306, p=0.021), but the correlation was no longer present after patients were treated by anti-psychotic agents. CONCLUSION: The S-100B levels of patients with schizophrenia are significantly higher than that of healthy controls, and the S-100B level is associated with severity of psychopathology, particularly negative symptoms, indicating that patients with schizophrenia may suffer structural damage to central nervous system. The concentration of S-100B may also be associated with treatment progress.

Recurrent de novo mutations of SCN1A in severe myoclonic epilepsy of infancy.

Mutations in the voltage-gated sodium channel gene SCN1A are a major cause of severe myoclonic epilepsy of infancy (Dravet syndrome) and generalized epilepsy with febrile seizures plus. This study reports the identification of six de novo SCN1A mutations in patients with severe myoclonic epilepsy of infancy, including a tetranucleotide deletion in exon 26. The same deletion was previously observed in two unrelated patients and appears to result from slipped-strand mispairing of a direct repeat during deoxyribonucleic acid replication. Review of the literature indicates that recurrent mutations account for 25% of SCN1A mutations in severe myoclonic epilepsy of infancy, including six sites of deamination at CpG dinucleotides.

Stratifying Risk for Renal Insufficiency Among Lithium-Treated Patients: An Electronic Health Record Study.

Although lithium preparations remain first-line treatment for bipolar disorder, risk for development of renal insufficiency may discourage their use. Estimating such risk could allow more informed decisions and facilitate development of prevention strategies. We utilized electronic health records from a large New England health-care system between 2006 and 2013 to identify patients aged 18 years or older with a lithium prescription. Renal insufficiency was identified using the presence of renal failure by ICD9 code or laboratory-confirmed glomerular filtration rate below 60 ml/min. Logistic regression was used to build a predictive model in a random two-thirds of the cohort, which was tested in the remaining one-third. Risks associated with aspects of pharmacotherapy were also examined in the full cohort. We identified 1445 adult lithium-treated patients with renal insufficiency, matched by risk set sampling 1 : 3 with 4306 lithium-exposed patients without renal insufficiency. In regression models, features associated with risk included older age, female sex, history of smoking, history of hypertension, overall burden of medical comorbidity, and diagnosis of schizophrenia or schizoaffective disorder (p<0.01 for all contrasts). The model yielded an area under the ROC curve exceeding 0.81 in an independent testing set, with 74% of renal insufficiency cases among the top two risk quintiles. Use of lithium more than once daily, lithium levels greater than 0.6 mEq/l, and use of first-generation antipsychotics were independently associated with risk. These results suggest the possibility of stratifying risk for renal failure among lithium-treated patients. Once-daily lithium dosing and maintaining lower lithium levels where possible may represent strategies for reducing risk.

Attitudes, knowledge, and perceptions of Chinese doctors toward drug abuse.

We assessed the attitudes, knowledge, and perceptions of Chinese doctors who worked with drug abusers to provide direction for planned drug and alcohol education and training. A 34-item questionnaire was developed; 523 copies were distributed and 446 (84.5%) validated copies were collected. Half of the respondents (50.0%) had no formal training before they started treating drug abusers. Among them, only 16.6% were psychiatrists. Less than half of the respondents agreed that drug abuse (addiction) is a brain disorder. Male and female doctors and doctors from different facilities tended to have different opinions on reasons for relapse, efficacy of treatments, and awareness of treatment modalities, among others. Doctors from involuntary facilities were more likely to disagree with the idea that drug addiction is a brain disorder and favored compulsory treatment. Doctors involved in drug abuse treatment in China are not well prepared or experienced in drug abuse treatment and have negative attitudes toward drug abuse and abusers.

Addictions and their familiality in Iceland.

Here, we provide an overview of previous family studies of addiction and present a new family study based on clinical data for more than 19,000 individuals who have been treated for addiction in Iceland over the last three decades. Coupled with the extensive Icelandic genealogy information, this population-based sample provides a unique opportunity for family studies. The relative risk (RR) was determined for up to fifth-degree relatives of probands diagnosed with alcohol, cannabis, sedative, and amphetamine dependence. We observe highly significant RR values for all substances ranging from 2.27 for alcohol to 7.3 for amphetamine, for first-degree relatives, and RRs significantly above 1 for distant relations, where the effect of shared environmental factors is minimized. The magnitude of risk in psychostimulant dependence is particularly striking. These findings emphasize the role of genetics in the etiology of addiction and highlight the importance of substance-specific effects.

Migrainous vertigo: mutation analysis of the candidate genes CACNA1A, ATP1A2, SCN1A, and CACNB4.

BACKGROUND: Migrainous vertigo (MV) is increasingly recognized as a common cause of episodic vertigo. MV displays several clinical similarities with familial hemiplegic migraine (FHM) and episodic ataxia type 2 (EA-2), which have been linked to mutations in 3 genes, CACNA1A, encoding a neuronal calcium channel alpha subunit, ATP1A2, encoding a catalytic subunit of a Na(+)/K(+)-ATPase, and most recently the voltage-gated sodium channel SCN1A. The present study explored the hypothesis that mutations in CACNA1A, ATP1A2, SCN1A, and the calcium channel beta(4) subunit CACNB4 confer susceptibility to MV. METHODS: Mutation analysis of the coding exons and exon/intron junctions of CACNA1A, ATP1A2, SCN1A, and CACNB4 was performed in 14 unrelated MV patients by conformation sensitive gel electrophoresis and automated sequence analysis. RESULTS: Analysis of the 4 candidate genes in the 14 MV patients resulted in the identification of a total of 26 sequence variants. The silent substitution D29D in CACNB4 was observed in 2 MV patients and was not present in 46 ethnically matched control DNA samples. The remaining variants were also observed in control DNA samples and the allele frequencies of variants that resulted in amino acid substitutions were not significantly different between patients and controls. CONCLUSIONS: Based on this group of patients there is no evidence that the genes causing FHM and EA-2 represent major susceptibility loci for MV.