K S Kendler

..Early onset of regular smoking is associated with an elevated risk for later nicotine dependence. Whether or not this association is causal is unknown and has substantial public policy implications...

..His goal of developing a consistent ‘ natural ’ classification of the major mental disorders has yet to be attained, but his ‘ research agenda' remains central to psychiatry to the present day...

..A complete understanding of the familial transmission of DA will require knowledge of how genetic and familial environmental risk factors act and interact over development...

..However, to our knowledge, no prior study has evaluated the underlying nature of the etiologic influences contributing to conduct disorder (CD) symptoms as defined in the DSM...

..Alcohol use disorders (AUDs) are clinically heterogeneous and strongly influenced by familial/genetic factors. Can we identify specific clinical features of AUDs that index familial liability to illness?..

..While tentative and in need of replication, these results, consistent with the rodent literature, were validated by examining predictions of the genetic factor scores and have implications for gene-finding efforts in AD...

..Critically, it is based not on how we wish the world to be but how the difference-makers for psychiatric illness are in fact distributed...

..Identifying these risk genes and understanding their action will require large clinical samples, and interaction between these studies and work in model organisms...

..In both cases, a complicated relationship between abstract constructs and evidence made the classification problem thorny...

..However, no prior study has examined the factor structure of the DSM-IV criteria for antisocial personality disorder (ASPD)...

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..While both environmental and genetic factors are important in the etiology of psychoactive substance use (PSU), we know little of how these influences differ through development...

..Analysis conducted using the Mx program included SxAnxDep by parental and self-report...

..A depressive episode that is bereavement-related and has clinical features and course characteristic of normal grief is not diagnosed as major depression. This study evaluates the empirical validity of this exclusion criterion...

..The authors sought to clarify the structure of the genetic and environmental risk factors for 22 DSM-IV disorders: 12 common axis I disorders and all 10 axis II disorders...

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..The sample is diverse and pair resemblance is generally similar to that obtained using interviews or mailed questionnaires...

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..Regardless of the starting point, if each iteration (or revision) improves the performance of the nosology, the eventual success of the nosologic process, to optimally reflect the complex reality of psychiatric illness, is assured...

..Major depresssion (MD) and coronary artery disease (CAD) frequently co-occur. The mechanisms of comorbidity are uncertain...

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..For other syndromes (e.g. schizophrenia), the context is generally irrelevant. Should the diagnosis of major depression (MD) be made dependent upon or independent of the psychosocial context in which it occurs?..

..The iterative process of interactions between biology and psychology needed to achieve this implementation will deepen our understanding of both classes of processes...

..While the nature of common fears changes over development, we do not know whether genetic effects on fear-proneness are developmentally stable or developmentally dynamic...

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..We have examined the relationship between the genetic and environmental risk factors for dimensional representations of these three personality disorders...

..For some behaviors, the pathway from genes to behavior differs meaningfully in males and females. With respect to the broad patterns of genetic influences on behavior, Homo sapiens appears to be typical of other animal species...

..Prior studies suggest that the personality traits of neuroticism and extroversion may be related to the liability to major depression (MD)...

..The personality trait of neuroticism (N) is substantially correlated with risk for MD and GAD...

..Accumulating evidence from developmental and genetic studies has made this perspective increasingly untenable...

..We wish to know whether the same set of PD vulnerability factors are assessed by these two methods...

..Although familial factors certainly contribute to the etiology of major depression (MD), further information is needed about which clinical features of depressive illness index the familial vulnerability in MD...

..While the role of genetic factors in self-report measures of emotion has been frequently studied, we know little about the degree to which genetic factors influence emotional facial expressions...

..Although levels of CD and PD are strongly correlated, the causal relationship between them has remained controversial and has not been examined by a genetically informative study...

..Although genetic risk factors have been found to contribute to dependence on both licit and illicit psychoactive substances, we know little of how these risk factors interrelate...

..Genetic and environmental risk factors for fears are partly shared across fears and partly fear-specific. The nature of the changes in common and fear-specific genetic and environmental risk factors over time is unknown...

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..We conclude that AU and AUDs in men are complex traits influenced by genetic, family, temperamental, and social factors, acting and interacting over developmental time...

..While genetic influences on alcohol dependence (AD) are substantial, progress in the identification of individual genetic variants that impact on risk has been difficult...

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..Can we address this question by using together 2 major methods for causal inference: natural experiments and specialized statistical methods?..

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..By middle adulthood, environmental experiences contributed substantially to stable and predictable interindividual differences in levels of anxiety and depression...

..No comprehensive etiologic model for SxAnxDep has illuminated the inter-relationship between their state- and trait-like characteristics, while including key predictor variables...

..Genetic factors impact substantially both on alcohol consumption (AC) and on the risk for alcohol dependence (AD). However, we know little about the degree to which measures of AC index the genetic risk for AD...

..However, our internal replications, when considered along with the positive results obtained in multiple other samples, suggests that most of these six regions are likely to contain genes that influence liability to schizophrenia...

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..In addition, we know little about the relationship of the familial risk factors for premenstrual symptoms and major depression...

..CONCLUSIONS: Prior psychiatric disorders are significant risk factors for the development of MDD, independent of the length of the intervening period between the onset of the first disorder and that of MDD...

..The familial aggregation of GAD in this sample was only modest. In the best-fitting models, the heritability of GAD was the same in men and women, estimated at about 15% to 20%, with no effects of gender-specific genes detected...

..This study replicates the original reported association of ZNF804A with schizophrenia and suggests that there is a consistent link between the A allele of rs1344706, increased expression of ZNF804A and risk for schizophrenia...

..Prior studies of twins reared together suggest that regular tobacco use (RTU) is substantially heritable. However, strong social influences on RTU might have biased these results...

..These data are not consistent with a strong etiological role for DRD5 in the etiology of these complex smoking behaviors...

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..Relatively little is known about the environmental and genetic contributions to gambling frequency and disordered gambling (DG), the full continuum of gambling-related problems that includes pathological gambling (PG)...

..Since CSF2RB is essential for IL3 signaling, the findings that both IL3 and CSF2RB showed sex-specific and FH-dependent associations suggest that the IL3 pathway is involved in schizophrenia...

..4). These results suggest a modest affective vulnerability conferred by this allele in psychosis, but will require replication...

..The authors sought to evaluate whether the pattern of schizophrenia and related disorders in probands and their relatives can be explained by a single underlying continuum of liability to the "schizophrenia spectrum."..

..Recent linkage studies suggest that multiple genes are important in the etiology of schizophrenia. The authors examined the hypothesis of whether the clinical variability in schizophrenia is due to genetic heterogeneity...

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..We present a method for summarizing the LD evidence, in any pedigree, that can be employed in trimmed-haplotype analysis as well as in other methods...

..If melancholia is a valid subtype of depression, is it quantitatively more severe than or qualitatively distinct from nonmelancholic depression?..

..However, account must be taken of the fact that family history reports are systematically biased. While promising, these results are preliminary and require replication...

..We concluded that COMT gene is associated with schizophrenia and carries a small but significant risk to the susceptibility in the Irish subjects...

..Implications of these findings for follow-up and replication studies are discussed...

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..Pregnancy and perinatal complications may be associated with an increased risk for eating disorders in women...

..Thus, in Irish families selected for a high density of schizophrenia, M-M LD may be very common within 0.5 cM and frequent up to distances of 2 cM...

..Our data suggests that the HTR1A gene may not play a major role in the genetic susceptibility underlying depressive and anxiety-related phenotypes...

..Subject to confirmation in an independent sample, our study suggests that variations in the GAD1 gene may contribute to individual differences in N and impact susceptibility across a range of anxiety disorders and major depression...

..The results suggest that the greater prevalence of major depression in women versus men is due neither to differences in the rates of reported stressful life events nor to differential sensitivity to their pathogenic effect...

..It was also found to be associated with the dysregulation of postsynaptic dopamine transmission, thus suggesting a potential role in several neuropsychiatric diseases...

..The authors sought to determine whether, in a general population sample, different categories of adverse life events were associated with different patterns of depressive symptoms...

..The pattern of lifetime comorbidity of common psychiatric and substance use disorders results largely from the effects of genetic risk factors...

..In this investigation, we explored four GABA receptor genes for their possible associations with genetic risk for anxiety disorders and depression...

..031) and QPDTPHASE (chi-square=12.54, p=.028). Also, a significant association between the GABRB3 191 bp allele and the hallucinations factor was detected using QPDTPHASE (chi-square=15.51, p=.030), but not QTDT (chi-square=2.07, p=.560)...

..Twin studies remain a vibrant part of the field of psychiatric genetics and an important complement to and context for current efforts to localize individual susceptibility genes...

..0038). More-modest support for linkage was observed for chromosome 10p, with logistic-regression analysis of linkage producing an empirical P=. 045 and with significant evidence for intersample heterogeneity (empirical P=.0096)...

..How does sex impact on the familial transmission of liability to fears and phobias?..

..The event dimensions that preceded mixed MD-GAS episodes were largely the sum of those that preceded pure MD and pure GAS episodes...

..Clarification of the nature of the causal links between low social support and depression in women is needed...

..Because of multiple testing, these results do not provide support for HTR2A as a susceptibility gene for psychotic illness, or for suicidal ideation within psychotic illness...

..Peer-group deviance is strongly associated with externalizing behaviors. We have limited knowledge of the sources of individual differences in peer-group deviance...

..Several possibilities, such as differing risk haplotypes, may explain this finding...

..Family environment probably has an impact on risk for agoraphobia and social phobia. The genetic liability to blood/injury phobias is not distinct from those of the more typical phobias...

..Genetic effects upon behaviour are pervasive. To what extent are the many correlates of major depression (MD) due to individual-specific environmental experiences versus genetic factors correlated with risk for MD?..

..Can a similar pattern be seen for the personality trait of Neuroticism (N)-which is a risk factor for many psychiatric conditions?..

..These results suggest that the PTEN gene may be involved in the etiology of both smoking initiation and nicotine dependence...

..This study was an attempt to replicate evidence for a vulnerability locus for schizophrenia and associated disorders in the 8p22-21 region reported by Pulver and colleagues...

..None of the four polymorphisms we tested, nor their estimated haplotypes, were associated with smoking initiation or progression to nicotine dependence...

..Developmental models of psychiatric illness should adopt an interactionist view of individuals and their environment (person and environment)...

..How do genetic risk factors for major depression impact on this "kindling" phenomenon? In particular, do those at high genetic risk exhibit an increase in the speed of kindling, or are they "prekindled"?..

..Are there risk factors that associate with illicit drug use or illicit drug abuse/dependence? Is the magnitude of the association the same for use and abuse/dependence? Does this pattern of association differ across categories of drugs?..

..We conclude that further investigation of dysbindin is warranted...

..An adoption study of alcoholism suggests that in women, the impact of genetic risk factors become greater in the presence of conflict in the family of origin. Is the same true for cigarette smoking (CS)?..

..The results suggest that for the population studied, additive genetic and unique environmental effects largely account for the variance across the religiosity construct...

..We report these results and combine them with those reported previously for the Copenhagen sample to form the National sample...

..The deficit syndrome may be a useful phenotype in genetic linkage studies...