Relationship between neuroticism personality trait and serotonin transporter binding.

BACKGROUND: Personality trait is thought to be one of the important factors for vulnerability to depression. The relation between serotonin transporter (5-HTT) polymorphism and anxiety-related personality has been investigated in genetic research. In this study, we investigated the relation between in vivo regional 5-HTT binding in the brain and personality inventory measures in normal male volunteers. METHODS: Thirty-one healthy male volunteers underwent positron emission tomography scans with (11)C-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl) benzonitrile ([(11)C]DASB) to measure 5-HTT and completed revised NEO Personality Inventory. Correlation of [(11)C]DASB binding potentials (BP) with personality inventory measures was calculated using region-of-interest analysis and statistical parametric mapping based on the BP images. RESULTS: Neuroticism was positively correlated with 5-HTT binding in the thalamus (p = .004). No significant correlation was observed in any other brain region. Within the neuroticism dimension, the facet of depression was positively correlated with 5-HTT binding in the thalamus (p = .001). CONCLUSIONS: Subjects with higher thalamic 5-HTT binding are more likely to express higher levels of neuroticism and depressive feeling. Serotonin transporter binding in the thalamus might be a marker of vulnerability to depression.     

Association between serotonin transporter gene and borderline personality disorder

Borderline personality disorder (BPD) is characterized by a pervasive pattern of instability in regulation of emotion, interpersonal relationships, self-image, and impulse control beginning in early adulthood. BPD affects about 1-2% of the general population and has a high mortality rate as a result of suicide and impulsive behaviour. The serotonin transporter gene (5-HTT) is considered as a candidate gene for BPD as multiple lines of evidence have suggested that it plays an important role in suicide, impulsive behaviour, and emotional liability. To test for an association between 5-HTT and BPD, we genotyped three common polymorphisms: the serotonin transporter linked promoter region (5-HTTLPR); a variable number of tandem repeat (VNTR) in intron 2, and a single nucleotide variant (A/G) within the LPR region. Eighty-nine Caucasian patients with BPD and 269 Caucasian healthy controls were analyzed. The program UNPHASED was used to compare allele and haplotype frequencies between cases and controls. Significant differences in allele frequencies of the VNTR marker (p=0.012) and haplotype frequencies (p=0.002) between patients and controls were found. Compared with healthy controls, patients with BPD showed higher frequencies of the 10 repeat of the VNTR marker and the S-10 haplotype, and lower 12 repeat and L(A)-12 haplotype. Our results suggest that the serotonin transporter gene may play a role in the aetiology of borderline personality disorder.     

Interaction between the serotonin transporter gene and neuroticism in cigarette smoking behavior

Cigarette smoking behavior is influenced by both personality traits and inherited factors. Previous research showed that neuroticism-a broad personality domain that includes anxiety, depression, impulsiveness and vulnerability-increases the risk of being a smoker, primarily because of difficulty in quitting. Neuroticism has also been associated with the 5-HTTLPR, a functional polymorphism in the promoter for the serotonin transporter gene. We used population and family-based methods to analyze the joint effects of the 5-HTTLPR and neuroticism on smoking behavior in a population of 759 never, current, and former smokers, all members of sib-pairs. Our main finding is that smoking behavior is influenced by an interaction between neuroticism and 5-HTTLPR genotype. Specifically, neuroticism was positively correlated with current smoking and negatively associated with smoking cessation in individuals and siblings with poorly transcribed 5-HTTLPR-S genotypes, but not in those with the more highly expressed 5-HTTLPR-L genotype. Individuals with both a 5-HTTLPR-S genotype and a high level of neuroticism had the greatest difficulty in quitting smoking. These data, if replicated, suggest that smoking behavior is more strongly influenced by the combination of the serotonin transporter gene and neuroticism than by either factor alone, and that personality scores and 5-HTTLPR genotype may predict the clinical efficacy of certain smoking cessation drugs.     

Association analysis between gene variants of the tyrosine hydroxylase and the serotonin transporter in borderline personality disorder

Abstract

objectives. For patients with borderline personality disorder (BPD), we previously reported an independent effect of the catechol-o-methyl-transferase (COMT) low-activity (Met¹⁵⁸) allele and an interaction with the low-expression allele of the deletion/insertion (short/long or S/L, resp.) polymorphism in the serotonin transporter-linked promoter region (5-HTTLPR). The purpose of the present study was to extend these findings to the tyrosine hydroxylase (TH) Val⁸¹Met single nucleotide polymorphism (SNP), the 5-HTTLPR S/L polymorphism incorporating the recently described functional A/G SNP within the long allele of the 5-HTTLPR (rs25531) as well as the variable number of tandem repeat (VNTR) polymorphism within intron 2 of the serotonin transporter gene (STin2). Methods. In 156 Caucasian BPD patients and 152 healthy controls, we tested for association between BPD and the TH Val⁸¹Met SNP, the 5-HTTLPR/rs25531 polymorphism, the STin2, the interaction of the TH Val⁸¹Met SNP with the tri-allelic 5-HTTLPR/rs25531, the interaction of the TH Val⁸¹Met SNP with STin2. Results. Between BPD patients and controls, we observed a slight over-representation of the TH Met⁸¹Met genotype in BPD patients compared to controls, but no statistically significant differences in genotype distribution of the individual markers after adjusting for multiple testing. Logistic regression analysis showed a lack of interaction between the TH Val⁸¹Met and the 5-HTTLPR/rs25531 as well as between the TH Val⁸¹Met and the STin2 polymorphism. Conclusions. These data do not suggest independent or interactive effects of the TH Val⁸¹Met, the 5-HTTLPR/rs25531, or the STin2 polymorphisms in BPD.     

强迫症与5-羟色胺转运体基因多态的关联分析

目的 探索汉族人群中5-羟色胺转运体SLC6A4基因多态与强迫症发病的关系。方法采用聚合酶链反应扩增片段长度多态技术测定120例强迫症患者(强迫症组)和130名健康人(对照组)的SLC6A4基因型。结果 强迫症组SLC6A4第2内含子及启动子的基因型多态分布与对照组间的差异有显著性(X2=6.70,P=0.035;X2=6.35,P=0.042);第2内含子等位基因频数分布与对照组之间的差异有非常显著性(X2=7.54,P=0.006);第2内含子的等位基因10,12/10基因型和启动子的L/L基因型与强迫症存在显著正关联[比数比(OR)值分别为2.24,2.12和3.57,P<0.05];强迫症组及对照组内不同性别间基因型分布的差异均无显著性(P>0.05)。结论 在汉族人群中SLC6A4基因可能与强迫症存在遗传关联,第2内含子的等位基因10和12/10基因型、启动子的L/L基因型可能是强迫症的风险因子。     

5-羟色胺转运体基因多态性与青少年抑郁症的关联研究

目的 探讨中国汉族青少年抑郁症与5-羟色胺转运体（5-HTY）基因的启动子区多态（5-HTTLPR）之间的关系。方法 应用聚合酶链式反应（PCR）扩增技术对84例青少年抑郁症患者和85例健康者进行基因型分析。结果 5-HTYLPR基因的3种基因型S／S,L／S和L/L在青少年抑郁症组的分布分别为57．1％,36．9％,6．0％;在对照组分别为57．6％,34．1％,8．2％,两组间差异无显著性（P〉0．05）。抑郁症组中S／S基因型患者HAMD自杀因子评分明显高于L／L和L／S型患者（P〈0.01）。结论 5-HTT基因多态性与青少年抑郁症无明显关联。抑郁症中携带S／S基因型患者的自杀风险相对比L／L型、L／S型患者高。     

Association between a serotonin transporter promoter polymorphism (5HTTLPR) and personality disorder traits in a community sample

Background

The serotonin transporter (SERT) polymorphism (5HTTLPR) has been reported to be associated with several psychiatric conditions. Specific personality disorders could be intermediate factors in the known relationship between 5HTTLPR and psychiatric disorders. This is the first study to test the association between this polymorphism and dimensions of all DSM-IV personality disorders in a community sample.

Methods

374 white participants were assessed by clinical psychologists using the International Personality Disorder Examination (IPDE). Associations between dimensions of each DSM-IV personality disorder and the long (l) and short (s) alleles of the 5HTTLPR were evaluated using non-parametric tests and regression models.

Results

The s allele of the 5HTTLPR polymorphism was significantly associated with higher avoidant personality trait scores in the whole sample. Males with the s allele had a significantly lower likelihood of higher obsessive-compulsive personality disorder (OCPD) trait scores, whereas females with the s allele were likely to have higher OCPD personality trait scores.

Conclusion

This paper provides preliminary data on the relationship between personality disorders and the 5HTTLPR polymorphism. The relationship of the s allele and avoidant PD is consistent with findings of a nonspecific relationship of this polymorphism to anxiety and depressive disorders. Concerning the unusual sexual dimorphic result with OCPD, several hypotheses are presented. These findings need further replication, including a more detailed study of additional variants in SERT.     

Association between serotonin transporter gene polymorphism and anxiety-related traits.

BACKGROUND: Polymorphism in the serotonin transporter promoter gene has been recently reported to be associated with the personality trait known as anxiety-related traits. We have attempted to replicate these findings in 101 healthy Japanese subjects. METHODS: The personality traits of the subjects were assessed with the tridimensional personality questionnaire. RESULTS: An association was observed in the present study between individuals grouped according to the transporter gene and harm avoidance scores. CONCLUSIONS: These data supported that there was an association between the serotonin transporter gene and anxiety.     

5-羟色胺转运体基因功能性多态与强迫症的关联研究

目的 探讨中国汉族人群中5-羟色胺转运体基因启动子区域多态(5-HTTLPR)功能性3等位基因L_A、L_G和S与强迫症(OCD)的关系.方法 采用聚合酶链反应-限制性片段长度多态技术测定138例OCD患者(OCD组)和199名健康人(对照组)的5-HTTLPR功能性3等位基因多态性.结果 OCD组5-HTTLPR功能性基因型及等位基因频率与对照组间的差异有统计学意义(χ~2=8.396,P＜0.05;χ~2=8.483,P＜0.01);L_A/L_A因型和L_A等位基因与OCD存在显著正关联[比值比分别为3.361(P＜0.05)和1.771(P＜0.01)].结论在中国汉族人群中5-HTTLPR功能性3等位基因可能与OCD存在遗传关联,L_A/L_A基因型和等位基因L_A可能是OCD的风险因子.     

Platelet serotonin uptake and paroxetine binding among allelic genotypes of the serotonin transporter in alcoholics

Expression rates of long (L) and short (S) alleles of the serotonin (5-HT) transporter (5-HTT) gene have been shown to differ under various circumstances. We compared 5-HTT uptake (function) level and paroxetine binding (density) in platelets of alcoholics as indices of 5-HTT expression rate among LL, LS, and SS genotypes. Concentration curves of [3H]5-HT and [3H]paroxetine were used to quantify the equilibrium constant (Km) and maximum 5-HT uptake rate (Vmax) for 5-HTT uptake into intact platelets and the dissociation constant (Kd) and maximum specific binding density (Bmax) for paroxetine binding to platelet membranes, respectively. Genotypes were determined using electrophoresis with fluorescent markers. Vmax for 5-HTT uptake did not correlate with Bmax for paroxetine binding (r=-0.095, P=0.415). Means of Vmax and Bmax did not differ in a statistically significant manner among LL, LS, and SS genotypes in these alcoholic subjects. However, Vmax for LL and SS appeared to have a bimodal distribution, so the percentage of subjects with Vmax <200 fmol/min-10(7) platelets was statistically significantly higher in LL than in SS (51.5% vs. 22.7%, respectively), with an odds ratio of 3.6 (P<0.05). The percentage of Vmax <200 fmol/min-10(7) platelets for LS was 39.3% (not significant vs. LL or SS). Previous studies of healthy human controls have shown that 5-HTT density in raphe nuclei and 5-HTT uptake in platelets are higher in the LL genotype than in S carriers. Our findings in currently drinking alcoholics support the hypothesis that those with the LL genotype of the 5'-HTTLPR region of the 5-HTT gene have reduced 5-HTT function.     

Association for serotonin transporter gene variable number tandem repeat polymorphism and schizophrenic disorders

In contrast with two previous western reports, a recent study on a Chinese population found an association for allele 12 of the variable number tandem repeat (VNTR) in the second intron of the serotonin transporter (5-HTT) gene and schizophrenic disorders. We have replicated this finding for a Chinese population in Taiwan (114 schizophrenic patients and 127 controls), demonstrating a modest but significant statistical association for the 5-HTT-VNTR allele 12 and schizophrenic patients (one-sided p = 0.043). This positive finding further supports the proposition that the 5-HTT-VNTR allele 12 is a risk factor for schizophrenic disorders in Chinese populations, although the effect is weak.     

Impulsive-disinhibited personality and serotonin transporter gene polymorphisms: Association study in an inmate’s sample

The association between different impulsive-disinhibited personality traits with 5-HTTLPR and 5-HTTVNTR genetic polymorphisms was examined in an imprisoned male sample. Higher scores of the impulsive-disinhibited personality traits tended to be associated with carrying one or two copies of the 5-HTTPLR S allele (S/S homozygous and S/L heterozygous), and carrying two copies of the 5-HTTVNTR 12 allele (12/12 homozygous). Genotype, allele, haplotype and extended genotype distribution between low and high impulsive-disinhibited groups confirmed this association. Allele S and genotypes S/S+S/L at the 5-HTTLPR locus and allele 12 and genotype 12/12 at the 5-HTTVNTR locus were overrepresented in the high scoring group. Accordingly, allele S and allele 12 conferred a trend for risk to be in the high scoring group with an odds ratio (OR) of 1.8 (p < 0.035) and 1.7 (p < 0.014), respectively. In addition, extended genotype distribution shows that those S allele carriers (S/S homozygote and S/L heterozygote) that were also 12/12 homozygote, were overrepresented in the high scoring group (OR = 3.2; p < 0.004). The main risk of being in the high scoring group was assigned to those carrying two copies of the S-12 haplotype (OR = 5.7; p < 0.0007). We discuss the possible relationship between the two genetic serotonin polymorphisms and the personality impulsive-disinhibited traits investigated.     

Genetic variation in serotonin transporter alters resting brain function in healthy individuals.

BACKGROUND: Perfusion functional magnetic resonance imaging (fMRI) was used to investigate the effect of genetic variation of the human serotonin transporter (5-HTT) gene (5-HTTLPR, SLC6A4) on resting brain function of healthy individuals. METHODS: Twenty-six healthy subjects, half homozygous for the 5-HTTLPR short allele (s/s group) and half homozygous for the long allele (l/l group), underwent perfusion functional and structural magnetic resonance imaging during a resting state. The two genotype groups had no psychiatric illness and were similar in age, gender, and personality scores. RESULTS: Compared with the l/l group, the s/s group showed significantly increased resting cerebral blood flow (CBF) in the amygdala and decreased CBF in the ventromedial prefrontal cortex. The effect of functional modulation in these regions by 5-HTTLPR genotype cannot be accounted for by variations in brain anatomy, personality, or self-reported mood. CONCLUSIONS: The 5-HTTLPR genotype alters resting brain function in emotion-related regions in healthy individuals, including the amygdala and ventromedial prefrontal cortex. Such alterations suggest a broad role of the 5-HTT gene in brain function that may be associated with the genetic susceptibility for mood disorders such as depression.     

中国大学生焦虑相关人格特质与5-羟色胺转运体基因多态性的相关性分析

目的调查5-羟色胺转运体基因上游调控区多态性位点(5-HTTLPR)与第二内含子多态性位点(5-HTTStin2)在中国汉族人群中的基因频率，比较这2个多态位点在种族间的差异，并且首次在中国大学生人群中对这2个多态位点与焦虑相关人格特质进行相关性研究。方法利用聚合酶链反应(PCR)等方法对222名随机健康汉族中国人中的这2个多态性位点进行了群体遗传学研究。并在148名大学生中对这2个位点与焦虑相关人格特质进行了相关分析。结果对于5-HTTLPR多态信息含量为0．352；5-HTTStin2多态信息含量为0．153。等位片段频率在中国汉族人与美国黑人及白人、西欧人、土耳其人有着显著差异，而与日本人相似。在148名大学生中进行的这2个位点与焦虑相关分析未能得出阳性结论。结论5-HTTLPR及5-HTTStin2这2个多态位点在不同种族和人群中的分布有差异；相关分析结果不支持在中国汉族人群中这2个多态位点与焦虑相关人格特质有关。     

载脂蛋白E,5—羟色胺转运体基因多态性与阿尔茨海默病的关 …

目的 探索载脂蛋白Ｅ（ａｐｏＥ）基因及５－羟色胺（５－ＨＴ）转运体基因多态性在阿尔茨海默病（ＡＤ）发病中的作用。方法 应用聚合酶链反应（ＰＣＲ）和限制性片段长度多态性方法,观察１０２例ＡＤ和１０５名正常对照组（对照组）的ａｐｏＥ基因多态性及２个５－ＨＴ转运体基因多态性的分布。结果 中,重度ＡＤ患者含ａｐｏＥ ε４基因型频率（２４％）高于对照组（１２％）,但差异无显著性（Ｘ＾２＝３．１７,Ｐ〈０．０