Association between serotonin transporter gene polymorphism and family history of attempted and completed suicide

The purpose of this study was to examine the association of the serotonin transporter gene to family history of suicidality. Forty-seven volunteers responded to questionnaires about family history of suicide, and provided buccal swabs for analysis of the polymorphism. Allelic homozygocity (the short variant) was associated with family history of suicidality. These data, to be interpreted with the study's limitations in mind, suggest a link between the serotonin transporter gene polymorphism and suicide-related variables, which should be the focus of future research.     

Association between intermale aggression and genetically-defined tryptophan hydroxylase activity in the mouse brain

The relationship between the genetically defined intensity of intermale aggression and the activity of brain tryptophan hydroxylase (TPH) has been studied in inbred mice. No association between the enzyme activity and the percentage of aggressive mice (reflecting the predisposition to aggressive reaction) was revealed. However, a significant positive interstrain correlation between brain TPH activity and accumulated attacking time (reflecting fight intensity) was identified. No correlation was found between TPH activity and the accumulated attacking time in segregating F2 (BALB × C57BL) mice. In conclusion, TPH is an important, but not the only factor controlling the intensity of intermale aggression in mice. © 1996 Wiley-Liss, Inc.     

Method choice, intent, and gender in completed suicide

Women who commit suicide use less violent methods, such as drugs and carbon monoxide poisoning, than do men, who more often use violent methods such as guns and hanging. Theories that attempt to explain this finding focus on gender differences in suicidal intent, socialization, emotions, interpersonal relationships, orientation and access to methods, and neurobiological factors. Data from a psychological autopsy study were used to test the theory that women who commit suicide use less violent means because they are less intent on dying. Although women were significantly less likely to use a violent method than men, there was no difference in the lethality of their suicidal intent.     

COMT基因Val158Met多态性与抑郁的关系

抑郁的发生具有重要的遗传学基础。COMT基因Val158Met多态性是抑郁的重要候选基因位点。目前有关COMT基因Val158Met多态性与抑郁关系的研究主要采用单基因设计、单基因-环境设计以及多基因-环境设计。有资料显示负性情绪偏向及其相关脑区可能在COMT基因Val158Met多态性与抑郁间起中介作用, 但具体机制仍有待探究。未来研究可以进一步考察被试的种族、年龄和性别等因素对COMT基因Val158Met多态性与抑郁关系的调节作用, 并通过采用多基因-环境设计, 综合运用积极与消极环境指标等措施深入考察负性情绪偏向和相关脑区在COMT基因Val158Met多态性与抑郁间的作用及其机制。     

Menninger's motives for suicide in the notes of completed and attempted suicides.

Brevard, Lester, and Yang in 1990, studying Menninger's motives for suicide, reported more evidence for the wish to be killed (i.e., self-blame or self-punishment) in suicide notes for completed suicides than in parasuicide notes for attempted suicide; however, they did not control for age and sex. A comparison of notes written by completed and attempted suicides that controlled for age and sex showed no differences in the presence of content which reflected Menninger's three motives for suicide, including the wish to be killed.     

Characteristics and VA health care utilization of U.S. Veterans who completed suicide in Oregon between 2000 and 2005

Oregon Violent Death Reporting System data were linked with Veterans Affairs (VA) administrative data to identify and describe veterans who completed suicide in Oregon from 2000 to 2005 (n = 968), and to describe their VA health care utilization in the year prior to death. Twenty-two percent had received health care in the VA system. Of these, 57% did not have mental health diagnoses and 58% had not seen mental health professionals. A larger proportion of those who accessed care were VA-enrolled and received service-connected disability benefits. Fifty-five veterans were hospitalized during the year prior to death. Of these, 33% completed suicide within 30 days of a hospitalization. Further development of suicide prevention strategies for veterans in the community, including general medical treatment settings, is indicated.     

Association between the HTR2B gene and the personality trait of fun seeking

Previous research reported that a rare serotonin receptor 2B gene (HTR2B) stop codon mutation predisposes subjects to severe impulsivity and novelty seeking. In this study, we expanded this previous work by testing six single nucleotide polymorphisms (SNPs) within the HTR2B gene for potential associations with the behavioral inhibition system (BIS) and the three components of the behavioral approach systems (BAS: fun seeking, drive, and reward responsiveness) in a Han Chinese sample (N = 478). Association analysis for individual SNPs indicated that four of the six SNPs (i.e., rs6437000, rs10194776, rs16827801, and rs1549339) were significantly associated with BAS fun seeking (p = .0003–.0022). Haplotype-based association analysis revealed that fun seeking was positively associated with haplotype A–A–G–A for SNPs rs6437000–rs10194776–rs16827801–rs1549339 (p = .0002), which survived Bonferroni correction. Except for the association between BAS reward responsiveness and rs16827801 (p = .005), no other association was found for BAS drive, BAS reward responsiveness, or BIS. This study provides the first evidence for the involvement of the HTR2B gene in BAS fun seeking. A better understanding of the genetic basis of the BIS and BAS would allow us to develop more effective diagnosis, treatment, and prevention of impulsive behavioral problems.     

The association between infants' self-regulatory behavior and MAOA gene polymorphism

Self-regulatory behavior in early childhood is an important characteristic that has considerable implications for the development of adaptive and maladaptive functioning. The present study investigated the relations between a functional polymorphism in the upstream region of monoamine oxidase A gene (MAOA) and self-regulatory behavior in a sample of Chinese infants at 6 months of age. Self-regulation was assessed by observing infants' behavior of orienting visual attention away from a threatening event in the laboratory situation. The results indicated that regulatory behavior was associated with the functional MAOA gene polymorphism in girls, but not boys. Girls with 4/4 genotypes displayed significantly higher regulation than girls with 3/3 and 3/4 genotypes. The present study provided evidence for gender differences on the role of MAOA gene polymorphism in socioemotional functioning in the early years.     

Association of national cancer mortality and suicide rates

Using WHO data from 1996 instead of 1990, the authors replicated and extended Knodrichin and Lester's 2001 study. Like their study, our total rates of cancer mortality and suicide in a similar sample of 37 European nations of the world were estimated to be positively associated.     

Association between MTHFR C677T polymorphism and depression: a meta-analysis in the Chinese population

Depression is a worldwide public health issue, and its prevalence increases each year. Although a number of studies have been conducted on the association between MTHFR C677T polymorphism and depression in China, this association remains elusive and controversial. To clarify the impact of MTHFR C677T polymorphism on the risk of depression, a meta-analysis was performed in the Chinese population. Relevant studies were identified using PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure and Chinese Biology Medicine through May 5, 2015. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. A total of 13 case–control studies including 1895 patients and 1913 controls were involved in this meta-analysis. Overall, T variant of MTHFR C677T gene polymorphism was significantly associated with an increased risk of depression in the Chinese population (T vs. C: OR = 1.52, 95% CI = 1.24–1.85; TT + CT vs. CC: OR = 1.64, 95% CI = 1.16–2.30; TT vs. CC: OR = 2.19, 95% CI = 1.49–3.24; TT vs. CC + CT: OR = 1.80, 95% CI = 1.31–2.46). In subgroup analyses stratified by geographic area and source of controls, the significant results were found in population-based studies, in hospital-based studies, in North and South China. The risk conferred by MTHFR C677T polymorphism is higher in North China than in South China. In conclusion, this meta-analysis suggests that MTHFR C677T polymorphism is associated with depression in the Chinese population, but these associations vary in different geographic locations.     

Association between obesity and suicide in woman,but not in man: a population-based study of young adults

The relationship between obesity and suicide risk is still unclear with controversial research results. The aim of this study is to investigate the relationship between obesity and suicide risk for men and women in a population-based study of young adults. This is a cross-sectional population-based study that identified young adults between 18 and 35 years of age. Suicide risk was investigated through the structured clinical interview Mini. Weight and height were assessed, and participants were classified as normal-weight body mass index (BMI < 30) or obese (BMI > 30). The prevalence of obesity was of 19.9% of the total sample (n = 1953). Obesity was more prevalent among women and participants between 27 and 35 years of age. Suicide risk was present in 13.0% of the sample and more prevalent among women. In our study we found an association between obesity and suicide risk for women, but not for men. Obesity was associated with a higher prevalence of suicide risk in women. Given the strength of the relationship between BMI and suicide, identifying the mechanisms associated with obesity, especially for women, can lead to new insights into the prevention of suicide risk     

Depressive rumination and the C957T polymorphism of the DRD2 gene

Depressed individuals who ruminate have difficulties learning from punishment and suppressing task-irrelevant information. The C957T polymorphism of the DRD2 gene, which affects functioning of D2 dopamine receptors (DRD2) that are expressed predominantly in the indirect pathway of the basal ganglia, has been found to influence suppression and punishment learning. Given these associations, we examined in the present study whether depressive rumination is related to the C957T polymorphism in 317 clinically depressed individuals and 317 never-depressed control individuals. A 2 × 2 (diagnostic group ×C957T polymorphism) analysis of variance conducted on depressive rumination scores yielded a significant interaction of group and C957T: Individuals with two 957C alleles reported higher levels of depressive rumination than did individuals with one or two 957T alleles if they were depressed, but not if they were healthy. The present findings suggest that the dopaminergic system and DRD2 are related to the frequency of maladaptive rumination in depressed individuals. Thus, DRD2 may be an important target for the pharmacological treatment of depressive rumination.     

The relationship between forgiveness and history of suicide attempt

The sentiment of forgiveness in relationship to suicide attempts/completions has been mostly examined through studies of suicide notes and the experiences of survivors and therapists – not attempters. In a cross-sectional sample of 304 consecutive primary care patients, we examined sentiments about forgiveness using the Forgiveness Scale, comparing those individuals with versus without past suicide attempts. According to findings, individuals with past suicide attempts (N?=?55; 19.1%) evidenced significantly lower composite scores on the Forgiveness Scale. As for individual items, compared to participants without past suicide attempts, those with past suicide attempts were significantly less believing of forgiveness by others, were less likely to forgive themselves, and to a lesser degree, were less forgiving of others. There were no between-group differences with regard to confession of wrongdoing or existential forgiveness by God. Findings may offer some salient avenues of therapeutic inquiry and endeavour in the psychological healing of individuals with past suicide attempts.     

The relationship between exposure to adolescent suicide and subsequent suicide risk. 2002 Student Award Address

In this study we examined the relationship between the exposure of adolescents to the suicide of a peer and subsequent suicide risk. Two hundred sixty-eight high school students filled out self-report questionnaires assessing demographic information, exposure to the suicide of a peer, relationship between survivor and suicide victim, and four measures of suicide risk (suicidal ideation, past and present suicide-related behavior, depressive symptomatology, and reasons for living). The 27 individuals who had been exposed to the suicide of a peer were classified as friends or acquaintances of suicide victims. Twenty-seven controls were then matched on gender, age, and ethnicity. The results of this study failed to support any of the hypothesized differences between exposed and unexposed adolescents of differing relationship categories on measures of suicide risk or depressive symptomatology. Three possible explanations for the results are evaluated and discussed within a conceptual framework.     

Association of serotonin transporter promoter gene polymorphism with violence: relation with personality disorders, impulsivity, and childhood ADHD psychopathology

There is evidence that disturbances in central serotonin (5-HT) function have a role in impulsive aggression, violence, and criminality. A deletion/insertion polymorphism within the 5-HT transporter (5-HTT) promoter gene (5-HTT gene-linked polymorphic region, 5-HTTLPR) is thought to be associated with several psychopathological phenotypes related to disturbed impulse control, anxiety and depression. This study examined the association of the 5-HTTLPR with violent behavior in a sample of 153 male Caucasians referred for a forensic psychiatric examination. We found a significant excess of the short (s) allele and the s/s genotype in patients characterized by recurrent and overt physical violent behavior. This genetic variance explained 5% of the variance of violent behavior. When controlled for the impact of several psychopathologies related to violent behavior, this association was observed in individuals with a history of childhood attention deficit/hyperactivity disorder (ADHD)-related symptoms, but not presenting with personality disorder or increased impulsiveness. In conclusion, the results (i). suggest an association between serotonergic dysfunction and violent behavior, (ii). provide evidence for an-at least partial-genetic regulation of violent behavior in a subgroup of male offenders, and (iii). suggest a significant role for 5-HT transporter functionality for violent behavior.