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Previous work has shown that school achievement is lower in children living in poor neighborhoods. In this study, the authors hypothesized a role of neighborhood social capital. Data on 11-year-olds were obtained from the baseline measurements of a family cohort study (n = 328). The data had a cross-level structure: neighborhood level, school level, and individual level. After including individual-level confounders, neighborhood socioeconomic disadvantage and social cohesion were not associated with school achievement in boys or girls. However, lower levels of neighborhood informal social control were associated with lower school achievement scores in boys only. In boys, a wider social environment that contributes to obedience to norms and values may be conducive to superior educational achievement. (Contains 4 tables.)

Previous work indicated protective effects of positive emotions on genetically influenced stress sensitivity. Given the fact that expression of brain-derived-neurotrophic-factor (BDNF) is associated with stress-induced behavioral changes, it was hypothesized that the BDNF [Val.sup.66]Met genotype may mediate genetic effects on stress sensitivity, conditional on the level of concurrent positive emotions. Subjects (n = 446) participated in a momentary assessment study, collecting appraisals of stress and affect in the flow of daily life. Multilevel regression analyses examined moderation of daily life stress-induced negative affect (NA) by BDNF genotype, and to what degree this was conditional on concurrent positive emotions. Results showed that heterozygous BDNF 'Met' carriers exhibited an increased NA response to social stress compared with 'Val/Val' subjects. Positive emotions at the time of the stressor decreased BDNF genetic moderation of the NA response to social stress in a dose-response fashion. This effect was most pronounced in BDNF Met carriers. Thus, the impact of BDNF genotype on stress sensitivity is conditional on the experience of positive emotions. Interdisciplinary research in psychology and psychiatric genetics may lead to the improvement of treatment choices in stress-related disorders. Keywords: BDNF [Val.sup.66]Met, gene-environment interaction, stress sensitivity, experience sampling method (ESM), positive emotions

Genetic moderation of experience of reward in response to environmental stimuli is relevant for the study of many psychiatric disorders. Experience of reward, however, is difficult to capture, as it involves small fluctuations in affect in response to small events in the flow of daily life. This study examined a momentary assessment reward phenotype in relation to the catechol-O-methyl transferase (COMT) Val158Met polymorphism. A total of 351 participants from a twin study participated in an Experience Sampling Method procedure to collect daily life experiences concerning events, event appraisals, and affect. Reward experience was operationalized, as the effect of event appraisal on positive affect (PA). Associations between COMT Val158Met genotype and event appraisal on the one hand and PA on the other were examined using multilevel random regression analysis. Ability to experience reward increased with the number of ‘Met’ alleles of the subject, and this differential effect of genotype was greater for events that were experienced as more pleasant. The effect size of genotypic moderation was quite large: subjects with the Val/Val genotype generated almost similar amounts of PA from a ‘very pleasant event’ as Met/Met subjects did from a ‘bit pleasant event’. Genetic variation with functional impact on cortical dopamine tone has a strong influence on reward experience in the flow of daily life. Genetic moderation of ecological measures of reward experience is hypothesized to be of major relevance to the development of various behavioral disorders, including depression and addiction.Neuropsychopharmacology (2008) 33, 3030–3036; doi:10.1038/sj.npp.1301520; published online 8 August 2007 [ABSTRACT FROM AUTHOR]

Previous work indicated protective effects of positive emotions on genetically influenced stress sensitivity. Given the fact that expression of brain-derived-neurotrophic-factor (BDNF) is associated with stress-induced behavioral changes, it was hypothesized that the BDNF Val66Met genotype may mediate genetic effects on stress sensitivity, conditional on the level of concurrent positive emotions. Subjects (n = 446) participated in a momentary assessment study, collecting appraisals of stress and affect in the flow of daily life. Multilevel regression analyses examined moderation of daily life stress-induced negative affect (NA) by BDNF genotype, and to what degree this was conditional on concurrent positive emotions. Results showed that heterozygous BDNF "Met" carriers exhibited an increased NA response to social Stress compared with "Val/Val" subjects. Positive emotions at the time of the stressor decreased BDNF genetic moderation of the NA response to social stress in a dose-response fashion. This effect was most pronounced in BDNF Met carriers. Thus, the impact of BDNF genotype on stress sensitivity is conditional on the experience of positive emotions. Interdisciplinary research in psychology and psychiatric genetics may lead to the improvement of treatment choices in stress-related disorders. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Psychotic patients with COMT Val158Met Met alleles were recently found to display more intense psychotic and affective responses to daily life stressors. We aimed to test the hypothesis that the Met allele is implicated in the development of affective and psychotic symptomatology in subjects genetically at risk for schizophrenia, by testing if unaffected first-degree relatives of patients with schizophrenia who share a Met allele have greater concordance of symptomatology than relatives not sharing a Met allele. Methods: Unaffected relatives (n =38) were arranged in as many genetically related pairs as possible (n =26), and Met-sharing between Index Unaffected Subject (IUS) and Related Unaffected Subject (RUS) was assessed. Symptomatology was assessed with the Brief Psychiatric Rating Scale (BPRS) total score. Results: Multilevel regression revealed an interaction between RUS BPRS score and Met-sharing in the model of IUS BPRS score (interaction χ 2 =3.78, p =0.05). Stratified analyses revealed that IUS–RUS total BPRS scores were significantly associated in the case of Met-sharing (B =0.57, 95% CI: 0.22–0.93, p =0.002), but were not when there was no Met-sharing. Conclusion: These findings support the hypothesis that the Met allele may be involved in the causation of psychopathology, at least in populations with a genetic predisposition to psychosis. [Copyright &y& Elsevier]

Genetic moderation of experience of reward in response to environmental stimuli is relevant for the study of many psychiatric disorders. Experience of reward, however, is difficult to capture, as it involves small fluctuations in affect in response to small events in the flow of daily life. This study examined a momentary assessment reward phenotype in relation to the catechol-O-methyl transferase (COMT) Val(158)Met polymorphism. A total of 351 participants from a twin study participated in an Experience Sampling Method procedure to collect daily life experiences concerning events, event appraisals, and affect. Reward experience was operationalized, as the effect of event appraisal on positive affect (PA). Associations between COMT Val(158)Met genotype and event appraisal on the one hand and PA on the other were examined using multilevel random regression analysis. Ability to experience reward increased with the number of 'Met' alleles of the subject, and this differential effect of genotype was greater for events that were experienced as more pleasant. The effect size of genotypic moderation was quite large: subjects with the Val/Val genotype generated almost similar amounts of PA from a 'very pleasant event' as Met/Met subjects did from a 'bit pleasant event'. Genetic variation with functional impact on cortical dopamine tone has a strong influence on reward experience in the flow of daily life. Genetic moderation of ecological measures of reward experience is hypothesized to be of major relevance to the development of various behavioral disorders, including depression and addiction.

Previous work indicated protective effects of positive emotions on genetically influenced stress sensitivity. Given the fact that expression of brain-derived-neurotrophic-factor (BDNF) is associated with stress-induced behavioral changes, it was hypothesized that the BDNF Val-sup-6-sup-6Met genotype may mediate genetic effects on stress sensitivity, conditional on the level of concurrent positive emotions. Subjects (n=446) participated in a momentary assessment study, collecting appraisals of stress and affect in the flow of daily life. Multilevel regression analyses examined moderation of daily life stress-induced negative affect (NA) by BDNF genotype, and to what degree this was conditional on concurrent positive emotions. Results showed that heterozygous BDNF "Met" carriers exhibited an increased NA response to social stress compared with "Val/Val" subjects. Positive emotions at the time of the stressor decreased BDNF genetic moderation of the NA response to social stress in a dose-response fashion. This effect was most pronounced in BDNF Met carriers. Thus, the impact of BDNF genotype on stress sensitivity is conditional on the experience of positive emotions. Interdisciplinary research in psychology and psychiatric genetics may lead to the improvement of treatment choices in stress-related disorders., (Copyright (c) 2008 APA, all rights reserved.)

Kaufman et al. [2006] reported a higher order interaction effect between specific genetic and environmental factors in a model of depressive symptoms, requiring independent replication. BDNF Val(66)Met and 5-HTTLPR genotypes were determined in female participants pertaining to a large ongoing twin study. Participants also filled in questionnaires on childhood adversity and depressive symptoms. Two- and three-way interactions between genetic polymorphisms and early adversity were examined in models of depressive symptoms. BDNF Met allele(s) moderated the effect of early adversity on depressive symptoms (two-way interaction), and this BDNF Met x childhood adversity interaction in turn was moderated by 5-HTTLPR genotype (three-way interaction). However, a main effect of BDNF Met on childhood adversity was also observed, possibly indicating confounding by gene-environment correlation. Higher order interaction effects involving BDNF Val(66)Met, 5-HTTLPR and childhood adversity may contribute to the etiology of depressive illness., ((c) 2007 Wiley-Liss, Inc.)