Deep Sequencing of 71 Candidate Genes to Characterize Variation Associated with Alcohol Dependence.

BACKGROUND: Previous genomewide association studies (GWASs) have identified a number of putative risk loci for alcohol dependence (AD). However, only a few loci have replicated and these replicated variants only explain a small proportion of AD risk. Using an innovative approach, the goal of this study was to generate hypotheses about potentially causal variants for AD that can be explored further through functional studies. METHODS: We employed targeted capture of 71 candidate loci and flanking regions followed by next-generation deep sequencing (mean coverage 78X) in 806 European Americans. Regions included in our targeted capture library were genes identified through published GWAS of alcohol, all human alcohol and aldehyde dehydrogenases, reward system genes including dopaminergic and opioid receptors, prioritized candidate genes based on previous associations, and genes involved in the absorption, distribution, metabolism, and excretion of drugs. We performed single-locus tests to determine if any single variant was associated with AD symptom count. Sets of variants that overlapped with biologically meaningful annotations were tested for association in aggregate. RESULTS: No single, common variant was significantly associated with AD in our study. We did, however, find evidence for association with several variant sets. Two variant sets were significant at the q-value <0.10 level: a genic enhancer for ADHFE1 (p = 1.47 × 10-5 ; q = 0.019), an alcohol dehydrogenase, and ADORA1 (p = 5.29 × 10-5 ; q = 0.035), an adenosine receptor that belongs to a G-protein-coupled receptor gene family. CONCLUSIONS: To our knowledge, this is the first sequencing study of AD to examine variants in entire genes, including flanking and regulatory regions. We found that in addition to protein coding variant sets, regulatory variant sets may play a role in AD. From these findings, we have generated initial functional hypotheses about how these sets may influence AD.

Deep Sequencing of Three Loci Implicated in Large-Scale Genome-Wide Association Study Smoking Meta-Analyses.

INTRODUCTION: Genome-wide association study meta-analyses have robustly implicated three loci that affect susceptibility for smoking: CHRNA5\CHRNA3\CHRNB4, CHRNB3\CHRNA6 and EGLN2\CYP2A6. Functional follow-up studies of these loci are needed to provide insight into biological mechanisms. However, these efforts have been hampered by a lack of knowledge about the specific causal variant(s) involved. In this study, we prioritized variants in terms of the likelihood they account for the reported associations. METHODS: We employed targeted capture of the CHRNA5\CHRNA3\CHRNB4, CHRNB3\CHRNA6, and EGLN2\CYP2A6 loci and flanking regions followed by next-generation deep sequencing (mean coverage 78×) to capture genomic variation in 363 individuals. We performed single locus tests to determine if any single variant accounts for the association, and examined if sets of (rare) variants that overlapped with biologically meaningful annotations account for the associations. RESULTS: In total, we investigated 963 variants, of which 71.1% were rare (minor allele frequency < 0.01), 6.02% were insertion/deletions, and 51.7% were catalogued in dbSNP141. The single variant results showed that no variant fully accounts for the association in any region. In the variant set results, CHRNB4 accounts for most of the signal with significant sets consisting of directly damaging variants. CHRNA6 explains most of the signal in the CHRNB3\CHRNA6 locus with significant sets indicating a regulatory role for CHRNA6. Significant sets in CYP2A6 involved directly damaging variants while the significant variant sets suggested a regulatory role for EGLN2. CONCLUSIONS: We found that multiple variants implicating multiple processes explain the signal. Some variants can be prioritized for functional follow-up.

Self- and parent-reported depressive symptoms rated by the mood and feelings questionnaire.

The Mood and Feelings Questionnaire (MFQ) was developed to measure depressive symptoms in children and adolescents. It includes a self-report and a parent-report part. This study set out to test the psychometric properties of the MFQ in a Danish population of children and adolescents.The study included a population-based sample of n = 992 individuals aged 9-17 years and n = 703 parents from five schools. The internal consistencies of both MFQ versions were excellent with high alpha coefficients. With few exceptions, correlation between items and the total score was moderate to high. Vegetative symptoms were among the lowest correlating items while cognitive symptoms were among the highest. Girls reported more depressive symptoms than boys, and reports from offspring indicated more depressive symptoms than reports from parents. There was no difference in depressive symptoms by respondents aged 9 to 11 compared to respondents aged 12 to 17 in schools where all pupils participated. However, in schools where pupils participated by choice, an increase in depressive symptoms by age was found. This study suggests that MFQ is reliable for evaluating depressive symptoms in a population of children and adolescents. Furthermore, it is of clinical relevance that parents tend to underreport depressive symptoms of their offspring.

Overlooked and underserved: "action signs" for identifying children with unmet mental health needs.

OBJECTIVE: The US Surgeon General has called for new approaches to close the mental health services gap for the large proportion of US children with significant mental health needs who have not received evaluation or services within the previous 6 to 12 months. In response, investigators sought to develop brief, easily understood, scientifically derived "warning signs" to help parents, teachers, and the lay public to more easily recognize children with unmet mental health needs and bring these children to health care providers' attention for evaluation and possible services. METHOD: Analyses of epidemiologic data sets from >6000 children and parents were conducted to (1) determine the frequency of common but severely impairing symptom profiles, (2) examine symptom profile frequencies according to age and gender, (3) evaluate positive predictive values of symptom profiles relative to Diagnostic and Statistical Manual of Mental Disorders diagnoses, and (4) examine whether children with 1 or more symptom profiles receive mental health services. RESULTS: Symptom-profile frequencies ranged from 0.5% to 2.0%, and 8% of the children had 1 or more symptom profile. Profiles generated moderate-to-high positive predictive values (52.7%-75.4%) for impairing psychiatric diagnoses, but fewer than 25% of children with 1 or more profiles had received services in the previous 6 months. CONCLUSIONS: Scientifically robust symptom profiles that reflect severe but largely untreated mental health problems were identified. Used as "action signs," these profiles might help increase public awareness about children's mental health needs, facilitate communication and referral for specific children in need of evaluation, and narrow the child mental health services gap.

Parents' Incomes and Children's Outcomes: A Quasi-Experiment.

We examine the role that an exogenous increase in household income due to a government transfer unrelated to household characteristics plays in children's long run outcomes. Children in affected households have higher levels of education in their young adulthood and a lower incidence of criminality for minor offenses. Effects differ by initial household poverty status. An additional $4000 per year for the poorest households increases educational attainment by one year at age 21 and reduces having ever committed a minor crime by 22% at ages 16-17. Our evidence suggests that improved parental quality is a likely mechanism for the change.