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Genetic Vulnerability (genetic + vulnerability)
Selected AbstractsPrediction of mortality at age 40 in Danish males at high and low risk for alcoholismACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2004J. Knop Objective:, This prospective high-risk study examined the influence of father's alcoholism and other archival-generated measures on premature death. Method:, Sons of alcoholic fathers (n = 223) and sons of non-alcoholic fathers (n = 106) have been studied from birth to age 40. Archival predictors of premature death included father's alcoholism, childhood developmental data, and diagnostic information obtained from the Psychiatric Register and alcoholism clinics. Results:, By age 40, 21 of the 329 subjects had died (6.4%), a rate that is more than two times greater than expected. Sons of alcoholic fathers were not more likely to die by age 40. Premature death was associated with physical immaturity at 1-year of age and psychiatric/alcoholism treatment. No significant interactions were found between risk and archival measures. Conclusion:, Genetic vulnerability did not independently predict death at age 40. Death was associated with developmental immaturities and treatment for a psychiatric and/or substance abuse problem. [source] Research Review: Genetic vulnerability or differential susceptibility in child development: the case of attachmentTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 12 2007Marian J. Bakermans-Kranenburg Gene,environment interactions interpreted in terms of differential susceptibility may play a large part in the explanation of individual differences in human development. Reviewing studies on the behavioral and molecular genetics of attachment, we present evidence for interactions between genetic and environmental factors explaining individual differences in attachment security and disorganization. In particular, the DRD4 7-repeat polymorphism seems associated with an increased risk for disorganized attachment, but only when combined with environmental risk. Gene,environment (G × E) interactions may be interpreted as genetic vulnerability or differential susceptibility. We found support for the differential susceptibility hypothesis predicting not only more negative outcomes for susceptible children in unfavorable environments, but also positive outcomes for susceptible children in favorable environments. [source] Genetic aspects of pathological gambling: a complex disorder with shared genetic vulnerabilitiesADDICTION, Issue 9 2009Daniela S. S. Lobo ABSTRACT Aims To summarize and discuss findings from genetic studies conducted on pathological gambling (PG). Methods Searches were conducted on PubMed and PsychInfo databases using the keywords: ,gambling and genes', ,gambling and family' and ,gambling and genetics', yielding 18 original research articles investigating the genetics of PG. Results Twin studies using the Vietnam Era Twin Registry have found that: (i) the heritability of PG is estimated to be 50,60%; (ii) PG and subclinical PG are a continuum of the same disorder; (iii) PG shares genetic vulnerability factors with antisocial behaviours, alcohol dependence and major depressive disorder; (iv) genetic factors underlie the association between exposure to traumatic life-events and PG. Molecular genetic investigations on PG are at an early stage and published studies have reported associations with genes involved in the brain's reward and impulse control systems. Conclusions Despite the paucity of studies in this area, published studies have provided considerable evidence of the influence of genetic factors on PG and its complex interaction with other psychiatric disorders and environmental factors. The next step would be to investigate the association and interaction of these variables in larger molecular genetic studies with subphenotypes that underlie PG. Results from family and genetic investigations corroborate further the importance of understanding the biological underpinnings of PG in the development of more specific treatment and prevention strategies. [source] Neurophysiological and genetic distinctions between pure and comorbid anxiety disorders,DEPRESSION AND ANXIETY, Issue 5 2008Mary-Anne Enoch M.D. Abstract Anxiety disorders are often comorbid with major depression (MD) and alcohol use disorders (AUD). Two common functional polymorphisms in catechol-O-methyltransferase (COMT Val158Met) and brain-derived neurotrophic factor (BDNF Val66Met) genes have been implicated in the neurobiology of anxiety and depression. We hypothesized that attentional response and working memory (auditory P300 event-related potential and Weschler Adult Intelligence Scale, Revised digit symbol scores) as well as genetic vulnerability would differ between pure anxiety disorders and comorbid anxiety. Our study sample comprised 249 community-ascertained men and women with lifetime DSM-III-R diagnoses. We analyzed groups of participants with pure anxiety disorders, pure MD, pure AUD, comorbid anxiety, and no psychiatric disorder. Participants were well at the time of testing; state anxiety and depressed mood measures were at most only mildly elevated. Individuals with pure anxiety disorders had elevated P300 amplitudes (P=0.0004) and higher digit symbol scores (P<0.0001) compared with all the other groups. Individuals with comorbid anxiety had the greatest proportion of COMT Met158 and BDNF Met66 alleles (P=0.009) as well as higher harm avoidance-neuroticism (P<0.0005) than all other groups. Our results suggest that there may be two vulnerability factors for anxiety disorders with differing genetic susceptibility: (a) heightened attention and better working memory with mildly elevated anxiety-neuroticism, a constellation that may be protective against other psychopathology; and (b) poorer attention and working memory with greater anxiety-neuroticism, a constellation that may also increase vulnerability to AUD and MD. This refinement of the anxiety phenotype may have implications for therapeutic interventions. Depression and Anxiety 0:1,10, 2007. Published 2007 Wiley-Liss, Inc. [source] Interrelationship of childhood trauma, neuroticism, and depressive phenotypeDEPRESSION AND ANXIETY, Issue 3 2007Valentina Moskvina Ph.D. Abstract Both childhood trauma (CT) and genetic factors contribute to the pathophysiology of depression. We studied the relationship of CT to age of onset (AO) of depression, personality traits, and expression of symptom dimensions in 324 adults with recurrent unipolar depression. Subjects received structured psychiatric interviews and completed CT, depressive symptom, and personality rating questionnaires. Experience of at least one type of trauma was reported by 79.9% of subjects, and the most common forms of trauma were physical neglect, emotional abuse, and emotional neglect. There was an earlier AO of depression in the groups that reported CT compared to those that reported none, with earliest AO occurring in those who had experienced the highest levels of CT. There were no significant correlations between overall CT scores and neuroticism or extraversion. Total CT was a significant (P=.008) predictor of the Mood symptom dimension, mostly accounted for by emotional abuse (P=.019), and physical neglect predicted the Anxiety symptom dimension (P=.002). All types of CT are commonly reported in individuals with depression, and emotional abuse and physical neglect, though previously less well identified, appear to have an important role in the pathogenesis of depressive disorders. The effect of CT on individuals with an underlying genetic vulnerability to depression may result in differences in depressive phenotype characterized by earlier AO of depression and the expression of specific depressive symptom dimensions. Depression and Anxiety 24:163,168, 2007. © 2006 Wiley-Liss, Inc. [source] Early cannabis use and DSM-IV nicotine dependence: a twin studyADDICTION, Issue 11 2008Arpana Agrawal ABSTRACT Background Evidence suggests that cannabis users are at increased risk for cigarette smoking,if so, this may potentially be the single most alarming public health challenge posed by cannabis use. We examine whether cannabis use prior to age 17 years is associated with an increased likelihood of DSM-IV nicotine dependence and the extent to which genetic and environmental factors contribute to this association. Methods A population-based cohort of 24,36-year-old Australian male and female twins (n = 6257, 286 and 229 discordant pairs) was used. The co-twin,control method, with twin pairs discordant for early cannabis use, was used to examine whether, after controlling for genetic and familial environmental background, there was evidence for an additional influence of early cannabis use on DSM-IV nicotine dependence. Bivariate genetic models were fitted to the full data set to quantify the genetic correlation between early cannabis use and nicotine dependence. Results The early cannabis-using twin was about twice as likely to report nicotine dependence, when compared to their co-twin who had experimented with cigarettes but had never used cannabis. Even when analyses were restricted to cannabis users, earlier age cannabis use onset conferred greater risk (1.7) for nicotine dependence than did later onset. This association was governed largely by common genetic liability to early cannabis use and nicotine dependence, as demonstrated by genetic correlations of 0.41,0.52. Conclusions Early-onset cannabis users are at increased risk for nicotine dependence, but this risk is attributable largely to common genetic vulnerability. There is no evidence for a causal relationship between cannabis use and nicotine dependence. [source] Priming Deficiency in Male Subjects at Risk for Alcoholism: The N4 During a Lexical Decision TaskALCOHOLISM, Issue 12 2009Bangalore N. Roopesh Background:, While there is extensive literature on the relationship between the P3 component of event-related potentials (ERPs) and risk for alcoholism, there are few published studies regarding other potentially important ERP components. One important candidate is the N4(00) component in the context of semantic processing, as abnormalities in this component have been reported for adult alcoholics. Method:, A semantic priming task was administered to nonalcohol dependent male offspring (18 to 25 years) of alcoholic fathers [high risk (HR) n = 23] and nonalcoholic fathers [low risk (LR) n = 28] to study whether the 2 groups differ in terms of the N4 component. Subjects were presented with 150 words and 150 nonwords. Among the words, 50 words (primed) were preceded by their antonyms (prime, n = 50), whereas the remaining 50 words were unprimed. For the analysis, N4 amplitude and latency as well as behavioral measures for the primed and unprimed words were considered. Results:, A significant interaction effect was observed between semantic condition and group, where HR subjects did not show N4 attenuation for primed stimuli. Conclusion:, The lack of N4 attenuation to primed stimuli and/or inability to differentiate between primed and unprimed stimuli, without latency and reaction time being affected, suggest deficits in semantic priming, especially in semantic expectancy and/or postlexical semantic processing in HR male offspring. Further, it indicates that it might be an electrophysiological endophenotype that reflects genetic vulnerability to develop alcoholism. [source] Variation in GABRA2 Predicts Drinking Behavior in Project MATCH SubjectsALCOHOLISM, Issue 11 2007Lance O. Bauer Background:, Previous studies demonstrated, and replicated, an association between single nucleotide polymorphisms (SNPs) within the GABRA2 gene and risk for alcohol dependence. The present study examines the association of a GABRA2 SNP with another definition of alcohol involvement and with the effects of psychosocial treatment. Methods:, European-American subjects (n = 812, 73.4% male) provided DNA samples for the analysis. All were participants in Project Matching Alcoholism Treatment to Client Heterogeneity (MATCH), a multi-center randomized clinical trial evaluating the efficacy of 3 types of psychosocial treatment for alcoholism: Cognitive Behavioral Therapy (CBT), Motivational Enhancement Therapy (MET), or twelve-step facilitation (TSF). The daily probabilities of drinking and heavy drinking were estimated during the 12-week treatment and 12-month post-treatment periods. Results:, Subjects homozygous for the allele associated with low risk for alcohol dependence in previous studies had lower daily probabilities of drinking and heavy drinking in the present study. This low-risk allele was also associated with a greater difference in drinking outcomes between the treatments. In addition, it enhanced the relative superiority of TSF over CBT and MET. Population stratification was excluded as a confound using ancestry informative marker analysis. Conclusions:, The assessment of genetic vulnerability may be relevant to studies of the efficacy of psychosocial treatment: GABRA2 genotype modifies the variance in drinking and can therefore moderate power for resolving differences between treatments. [source] Genetic diversity among parental lines of Indica hybrid rice (Oryza sativa L.) in China based on coefficient of parentagePLANT BREEDING, Issue 6 2006S. Wang Abstract Genetic diversity constitutes the raw material for plant improvement, and provides protection against genetic vulnerability to biotic and abiotic stresses. Diversity of parental lines of indica hybrid rice in China is not well-characterized. The major objective of this study was to quantify genetic diversity of Chinese parental lines of hybrid rice via coefficient of parentage (COP). All 100 parental lines of hybrid rice widely used in hybrid breeding and commercial production during 1976,2003 were studied by COP analysis. The mean COP for the 100 parental lines was low (0.056), indicating a potentially high degree of diversity in Chinese hybrid rice breeding. Forty-nine percent of all pairs of parental lines were completely unrelated by pedigree data. The low mean COP for the parental lines was attributed to a continual incorporation of exotic germplasm (wild rice, japonica and javanica etc.) into the genetic base over time, to the introduction of foreign germplasm from the Philippines (International Rice Research Institute), Korea, the United States, Thailand, and Guyana as breeding stock. The mean COP from 1976 to 1990 was twice as much as that from 1990 to 2003. Cluster analysis was an effective method to discriminate diversity, ten clusters were identified, and maintainer lines, restorer lines and other parental lines with special genetic background were clearly grouped. In addition, restorer lines were further divided into 11 sub-clusters, which basically was in agreement with hybrid rice breeding. Among ten provinces, Hunan, Sichuan and Fujian were outstanding for breeding 54 of 100 parental lines in hybrid rice production, and the genetic diversity of parental lines in Fujian, Sichuan,Guangxi, Hunan and Jiangsu were all narrower than that in Hubei, Guangdong, Zhejiang and Jiangxi. The result of coefficient of parentage analysis for 100 parental lines may promote the management of parental diversity and hybrid rice breeding in China. [source] Intra-episode hypomanic symptoms during major depression and their correlatesPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2004FRANCO BENAZZI md Abstract Recent studies have shown that 40,50% of major depressive disorders (MDD) may become bipolar with time. Intra-episode hypomanic symptoms in MDD may be a first step in this shift. The purpose of the present study was to find factors associated with intra-episode hypomanic symptoms in MDD. Two hundred and forty-three consecutive MDD outpatients were interviewed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (4th edn; DSM-IV), Clinician Version (SCID-CV), as modified by Benazzi and Akiskal (J. Affect. Disord. 2003; 73: 33,38). History of hypomania and presence of hypomanic symptoms during major depressive episode (MDE) were systematically assessed. Intra-episode hypomanic symptoms were defined as an MDE combined with three or more hypomanic symptoms, following Akiskal and Benazzi (J. Affect. Disord. 2003; 73: 113,122). Major depressive disorder with intra-episode hypomanic symptoms (MDD + H) was compared to MDD without hypomanic symptoms on classic bipolar validators. It was found that MDD + H (usually irritability, distractibility, racing thoughts, psychomotor agitation, and more talkativeness) was present in 32.5% of patients. Patients with MDD + H versus MDD had significantly lower age at onset, more atypical depressions, and more bipolar family history. Recurrences were not significantly different. Multivariate logistic regression found that bipolar family history and atypical depression were significantly and independently associated with MDD + H. Findings suggest that MDD + H may be associated with a bipolar vulnerability. Duration of illness and recurrences do not seem to be important for the onset of MDD + H. Bipolar genetic vulnerability seems to be required for onset of intra-episode hypomanic symptoms in MDD. Intra-episode hypomanic symptoms might be the first step of a process leading to the switch of MDD to bipolar disorders. Predicting the switch might have important treatment implications, because antidepressants used alone may worsen the course of bipolar disorders. Prospective studies are required to support these findings and hypotheses. [source] Research Review: Genetic vulnerability or differential susceptibility in child development: the case of attachmentTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 12 2007Marian J. Bakermans-Kranenburg Gene,environment interactions interpreted in terms of differential susceptibility may play a large part in the explanation of individual differences in human development. Reviewing studies on the behavioral and molecular genetics of attachment, we present evidence for interactions between genetic and environmental factors explaining individual differences in attachment security and disorganization. In particular, the DRD4 7-repeat polymorphism seems associated with an increased risk for disorganized attachment, but only when combined with environmental risk. Gene,environment (G × E) interactions may be interpreted as genetic vulnerability or differential susceptibility. We found support for the differential susceptibility hypothesis predicting not only more negative outcomes for susceptible children in unfavorable environments, but also positive outcomes for susceptible children in favorable environments. [source] |