An interaction between the norepinephrine transporter and monoamine oxidase A polymorphisms, and novelty-seeking personality traits in Korean females

The personality traits associated with the noradrenergic system have not yet been clearly established. In the present study, we investigated the variable number of tandem repeats (VNTR) polymorphism of the norepinephrine transporter (NET) and monoamine oxidase A (MAOA), which are major components of the adrenergic system, to elucidate their relationship with personality. A total of 245 normal female Koreans (age 23.05+/-3.07 years, mean+/-SD) volunteered to take part in this study. They filled out a Korean version of the Temperament and Character Inventory (TCI) and were genotyped for the NET and MAOA-VNTR; the NET T-182C and MAOA-uVNTR polymorphisms were checked. We found significant main effect of NET genotype on novelty seeking (NS) score (F=5.43, p=0.021) and significant interaction between the NET and MAOA-uVNTR polymorphisms on NS score (F=11.06, p=0.001). However, there were no relationship between MAOA-uVNTR polymorphisms and NS score, and no association with other temperamental dimensions and these two polymorphisms. Our findings suggest that this functional polymorphism in the noradrenergic gene is associated with novelty seeking in Korean females.     

Association between monoamine oxidase A (MAOA) and personality traits in Japanese individuals

It has been reported that personality traits are related to several neurotransmitters. However, the association between personality traits and the central nervous system remains unclear. In the present study, we investigated the relationships between a polymorphism involving a variable number of tandem repeats in the promoter of the monoamine oxidase A (MAOA-VNTR) gene and personality traits, as assessed by the Temperament and Character Inventory (TCI). Promoter VNTRs in the MAOA were genotyped in 558 healthy Japanese individuals. Females homozygous for high-activity allele (4/4) had significantly higher persistence scores than those homozygous for the low-activity allele (3/3) (p=0.012, ANOVA). Meanwhile no difference in persistence was found between 3 and 4 allele in males. There were no differences between other scores of TCI subscales and MAOA-VNTR polymorphism. Our results suggest a gender-specific contribution of MAOA-VNTR polymorphism to persistence scores.     

Thrombocyte monoamine oxidase activity and personality traits in women with severe premenstrual syndrome

Women with premenstrual syndrome (PMS) of such severity that they actively had sought medical attention for their symptoms were compared with healthy female students with regard to platelet MAO activity and temperamental correlates by means of the Karolinska Scales of Personality (KSP), scales from the Eysenck Personality Questionnaire (EPQ) and Eysenck's IVE inventory. The women with PMS were divided into two groups; irritability and depression as predominating symptom. No variation in platelet MAO was found during the menstrual cycle, either in patients or in controls. Both PMS groups had significantly lower platelet MAO activity than the controls. There was no difference between the two groups with PMS. Also with regard to personality traits there were considerable differences between the females with PMS and the controls. There were few differences between the two groups of PMS patients. Thus, the patients scored significantly higher as regards somatic anxiety, muscular tension, indirect aggression, verbal aggression and neuroticism and lower as regards socialization than the controls.     

A regulatory monoamine oxidase a promoter polymorphism and personality traits

Monoamine oxidase type A (MAOA) has been implicated to be part of mechanisms underlying human temperament and psychiatric disorders. We hypothesised that a functional polymorphism in the 5' untranslated region of the MAOA gene is associated with specific personality traits. In 371 healthy Caucasians, we estimated personality traits by the use of the Karolinska Scales of Personality (KSP), Scandinavian Universities Scales of Personality, Health-Relevant 5-Factor Personality inventory, Temperament and Character Inventory and the revised NEO Personality Inventory. In the same subjects, we analysed the genotype of a polymorphic region consisting of a variable number of a 30-bp repeat sequence located approximately 1.2 kb upstream of the MAOA gene. After correction for multiple testing, no statistically significant differences between MAOA genotype and personality were observed in men (n = 206) nor in women (n = 165). We conclude that the structure of this MAOA promoter region does not have a large impact on the expression of personality characteristics in the present Swedish population.     

5-羟色胺转运体基因和单胺氧化酶A基因多态性与汉族男性反社会人格障碍患者的关联分析

目的 探讨5-羟色胺转运体基因(5-HTT)第2内含子的一个可变数串联重复序列(Stin2.VNTR)和单胺氧化酶A(MAOA)基因14外显子上的一种限制性片段长度多态性(EcoRV-RFLP)与汉族男性反社会人格障碍(APD),尤其是具有高度冲动性APD的遗传易感性的关系.方法 (1)APD组:对南京地区某监狱男性服刑人员进行人格诊断问卷(PDQ-4+)调查,在PDQ得分为阳性的可疑人群中由临床医师以美国精神障碍诊断与统计手册第4版(DSM-Ⅳ)关于APD诊断标准进一步确诊,入组118例;全部进行Barratt冲动量表(BIS-11)评分,以冲动总分中位值为界,划分为高冲动APD组和低冲动APD组.(2)监狱对照组:经PDQ排除人格障碍的250名服刑人员作为监狱内对照.(3)正常对照组:同时期医院健康体检者300名设为正常对照.取所有人员血液标本提取DNA,应用聚合酶链反应(PCR)和限制性片段长度多态性方法,对等位基因频率和基因型频率进行对比分析.结果 (1)APD组与正常对照组比较,5-HTT-VNTR基因型多态、MAOA-EcoRV-RFLP多态差异无统计学意义(x2=2.819,P=0.244;x2=2.347,P=0.126).(2)高冲动APD组与正常对照组比较,5-HTT-VNTR基因型多态差异有统计学意义(x2=7.422,P=0.024),MAOA-EcoRV-RFLP的等位基因频率有统计学意义(x2=5.478,P=0.019).(3)2个位点的联合分析中,APD组和高冲动APD组分别与对照组比较,12/12/-多倍体型的差异均有统计学意义(x2=7.164,P=0.007;x2=9.590,P=0.002);12/10/+仅在高冲动APD组与正常对照组间差异有统计学意义(x2=5.378,P=0.020).结论 5-HTT基因第2内含子VNTR多态、MAOA基因EcoRV-RFLP多态与具有高冲动的APD关联,12/12/-多倍体型与中国汉族男性APD发病风险可能有关.     

Association between serum levels of C-reactive protein and personality traits in women

Background  

While low-grade inflammation has consistently been observed in subjects with depression, studies on the possible relationship between inflammation and other aspects of brain function are as yet sparse. In this study, we aimed to investigate the possible association between serum levels of the inflammation marker C-reactive protein (CRP) and personality traits.     

Association between bipolar disorder and monoamine oxidase A gene polymorphisms: results of a multicenter study

OBJECTIVE: Although genetic factors have been implicated in the etiology of bipolar disorder, no specific gene has been conclusively identified. Given the link between abnormalities in serotonergic neurotransmission and bipolar disorder, a candidate gene association approach was applied to study the involvement of the monoamine oxidase A (MAOA) gene, which codes for a catabolic enzyme of serotonin, in the susceptibility to bipolar disorder. METHOD: In France and Switzerland, 272 patients with bipolar disorder and 122 healthy subjects were typed for three polymorphic markers of the MAOA gene: the MAOA-CA repeat, the MAOA restriction fragment length polymorphism (RFLP), and a repeat directly adjacent to the variable number of tandem repeats (VNTR) locus. RESULTS: A significant difference in the distribution of the alleles for the MAOA-CA repeat was observed between the female bipolar patients and comparison group. CONCLUSIONS: The results obtained in the French and Swiss population confirm findings from two studies conducted in the United Kingdom.     

MAOA and MAOB polymorphisms and anger-related traits in suicidal participants and controls

MAOA and, to a lesser extent, MAOB polymorphisms have been related to aggression traits and suicidality. We aimed to investigate the role of MAOA and MAOB in suicidal versus non-suicidal participants and interactions between genetic variation and suicidal status on aggression and anger-related traits. The sample was composed of three groups: one group of suicide attempters (n = 171, males 35.1 %), one group of suicide completers (n = 90, males 57.8 %) and a healthy control group (n = 317, males 43.8 %). We examined the following markers: MAOA rs909525, rs6323, and rs2064070, and MAOB rs1799836. Anger traits were measured with the state-trait anger expression inventory (STAXI) and aggression traits with the questionnaire for measuring factors of aggression (FAF). Associations were separately examined for males and females. Variation in the three MAOA variants was associated with higher levels of anger expressed outwards (STAXI “anger-out” subscale) in male suicidal patients compared to controls (p < 0.001). In females, the C allele of rs6323 showed higher scores on the same subscale (“anger out”) (p = 0.002). Allele frequencies of the MAOA rs909525 were associated with suicidality (p < 0.007). Our findings show an association between genetic variation in three polymorphisms of the MAOA and anger traits in suicidal males and one replication for the functional variant rs6323 in females. This relationship was stronger than a direct genetic association with suicide status. Future studies incorporating endophenotypic measures of anger and aggression in suicidal participants are warranted.     

Association of anger-related traits with SNPs in the TPH gene

Since both aggression-related traits and serotonergic activity are partially heritable and correlate inversely, variations in genes of the serotonergic system might then, to some extent, account for variations in aggression-related behavior. Tryptophan hydroxylase (TPH) is the rate limiting biosynthetic enzyme in the serotonin pathway and regulates levels of serotonin. Recently, a genetic variation in TPH has been associated with aggression and anger-related traits in volunteers. We investigated a sample of community-based healthy volunteers (n = 154) and suicide attempters (n = 86), a clinical population with a high risk for elevated impulsive aggression and related traits. The subjects were genotyped for a A218C and a A779C single nucleotide polymorphism (SNP) located in the TPH gene. All subjects were administered standard psychiatric interviews as well as self-report questionnaires for aggression, irritability and anger-related traits. For anger-related traits, a multivariate effect of the tryptophan hydroxylase genotype and an interaction effect for genotype and diagnosis was observed in healthy volunteers and suicide attempters after controlling for age and educational level. U-carriers in both groups showed higher scores for State Anger, Trait Anger and Angry Temperament. These findings support the hypothesis that the A218C and the A779C SNP in the TPH gene may be associated with anger-related traits in German samples.     

Association between dopaminergic polymorphisms and borderline personality traits among at-risk young adults and psychiatric inpatients

Background  

In the development of borderline personality disorder (BPD) both genetic and environmental factors have important roles. The characteristic affective disturbance and impulsive aggression are linked to imbalances in the central serotonin system, and most of the genetic association studies focused on serotonergic candidate genes. However, the efficacy of dopamine D2 receptor (DRD2) blocking antipsychotic drugs in BPD treatment also suggests involvement of the dopamine system in the neurobiology of BPD.     

Negative emotionality: monoamine oxidase B gene variants modulate personality traits in healthy humans

Monoamine oxidase A and B (MAOA and MAOB) appear to be involved in the pathogenesis of Major Depression, and vulnerability of Major Depression is associated with personality traits relating to positive and negative affect. This study aimed to investigate associations between MAOA and MAOB polymorphisms and personality traits of positive and negative emotionality in healthy volunteers, to elucidate mechanisms underlying personality and the risk for depression. Healthy Caucasian volunteers (N = 150) completed the Multiphasic Personality Questionnaire (MPQ), which includes independent superfactors of Positive Emotionality and Negative Emotionality. Participants were genotyped for 8 MAOA and 12 MAOB single nucleotide polymorphisms (SNPs). Association analyses for both SNPs and haplotypes were performed using the permutation approach implemented in PLINK. Negative Emotionality was significantly associated with the two highly linked MAOB polymorphisms rs10521432 and rs6651806 (p < 0.002). Findings were extended in haplotype analyses. For MAOB the 4-SNP haplotype GACG formed from rs1799836, rs10521432, rs6651806 and rs590551 was significantly related to lower Negative Emotionality scores (p < 0.002). MAOA was not related to personality in this study. Our finding provides the first evidence that MAOB polymorphisms influence levels of negative emotionality in healthy human volunteers. If confirmed, these results could lead to a better understanding of personality traits and inter-individual susceptibility developing psychiatric disorders such as major depression.     

Association between a promoter variant in the monoamine oxidase A gene and schizophrenia

Monoaminergic transmission has been implicated in the pathophysiology of schizophrenia. We investigated a putative functional promoter polymorphism in the monoamine oxidase A (MAOA) gene in schizophrenic patients (n=133) and control subjects (n=377). In men, there was an association between the less efficiently transcribed alleles and schizophrenia (chi(2)=4.01, df=1, p<0.05). In women, no significant differences were found. The present results support the involvement of the MAOA gene in men with schizophrenia in the investigated Swedish population but should be interpreted with caution until replicated.     

Association between a dinucleotide repeat polymorphism of the estrogen receptor alpha gene and personality traits in women

Estrogens are known to play a key role in the regulation of various aspects of behavior. In order to study the potential contribution of genetic variation in the estrogen receptor (ER) alpha to specific personality traits, we investigated a repeat polymorphism in the ER alpha gene in 172 42-year-old women who had been assessed using the Karolinska Scales of Personality (KSP). Based on the hypothesis that there is a relationship between the length of a repeat polymorphism and gene function,(1) the alleles were divided into two groups: short and long. In order to elucidate the possible influence of the ER alpha gene on the different aspects of personality measured by means of the KSP, the possible association between this gene and four different factors ('neuroticism', 'psychoticism', 'non-conformity', and 'extraversion') was analysed. 'Neuroticism', 'psychoticism', and 'non-conformity' all appeared to be associated with the ER alpha gene. After correction for multiple comparisons by means of permutation analysis, the associations with the factor 'non-conformity'--including the subscales 'indirect aggression' and 'irritability'--and the factor 'psychoticism'--including the subscale 'suspicion'--remained significant. The results suggest that the studied dinucleotide repeat polymorphism of the ER alpha gene may contribute to specific components of personality.     

Association between personality traits and Escitalopram treatment efficacy in panic disorder

Background: There is strong evidence to suggest that personality factors may interact with the development and clinical expression of panic disorder (PD). A greater understanding of these relationships may have important implications for clinical practice and implications for searching reliable predictors of treatment outcome.

Aims: The study aimed to examine the effect of escitalopram treatment on personality traits in PD patients, and to identify whether the treatment outcome could be predicted by any personality trait.

Method: A study sample consisting of 110 outpatients with PD treated with 10–20?mg/day of escitalopram for 12 weeks. The personality traits were evaluated before and after 12 weeks of medication by using the Swedish universities Scales of Personality (SSP).

Results: Although almost all personality traits on the SSP measurement were improved after 12 weeks of medication in comparison with the baseline scores, none of these changes reached a statistically significant level. Only higher impulsivity at baseline SSP predicted non-remission to 12-weeks treatment with escitalopram; however, this association did not withstand the Bonferroni correction in multiple comparisons.

Limitations: All patients were treated in a naturalistic way using an open-label drug, so placebo responses cannot be excluded. The sample size can still be considered not large enough to reveal statistically significant findings.

Conclusions: Maladaptive personality disposition in patients with PD seems to have a trait character and shows little trend toward normalization after 12-weeks treatment with the antidepressant, while the association between impulsivity and treatment response needs further investigation.     

囊泡单胺转运蛋白2基因多态性与帕金森病患者抑郁状态相关性的研究

目的 研究囊泡单胺转运蛋白2（VMAT2）的rs363371和rs363324基因多态性与汉族人群中PD患者合并抑郁状态的相关性。方法 收集102例汉族帕金森病（PD）患者,通过采用17项汉密尔顿抑郁量表（HAMD-17）将患者分为PD合并抑郁组和PD未合并抑郁组,用连接酶法对VMAT2的rs363371和rs363324进行了基因型分型,运用二元Logistic回归检验分析PD患者合并抑郁的危险因素。结果 rs363371的AA基因型降低了PD患者合并抑郁的风险（OR=0.22,59%CI 0.07-0.75,P=0.015）。UP3的高分值增加了PD患者合并抑郁的风险（OR=1.08,59%CI 1.02-1.15,P=0.009）。较长的病程增加了PD患者合并抑郁的风险（OR=1.15,59%CI 1.01-1.31,P=0.038）。rs363324的基因多态性并未增加PD合并抑郁的风险。结论 VMAT2的rs363371的AA基因型降低了汉族人群PD患者合并抑郁的风险。     

Low platelet monoamine oxidase activity in borderline personality disorder

Platelet monoamine oxidase (MAO) activity was significantly lower in nonpsychotic, nonorganic, unmedicated male inpatients with DSM-III-R borderline personality disorder (BPD) than in nonpsychiatric controls. Patients with BPD who also met DSM-III-R criteria for antisocial personality disorder had significantly lower MAO activity than those with BPD alone. Low MAO activity in this sample did not appear to be related to the comoroid presence of major depressive disorder or a history of substance abuse.     

单胺氧化酶B基因多态与早发帕金森病的相关性

目的 探讨单胺氧化酶B(MAO-B)基因型和等位基因与早发帕金森病(early-onset Parkinson's disease,EOPD)的关系.方法 采取聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的方法,研究65例EOPD患者(<50岁)、60例晚发PD(late-onset Parkinson's disease,LOPD)患者(≥60岁)和66名健康对照者(<50岁)的基因型频率和等位基因频率的分布差异.结果 EOPD组的AA基因型频率(49/65,75.4%)高于健康对照组(34/66,51.5%),差异有统计学意义(x2=8.075,P=0.018);LOPD组分别与EOPD组、健康对照组的从基因型频率比较,差异无统计学意义;男性EOPD组分别与男性健康对照组、男性LOPD组,女性EOPD组分别与女性健康对照组、女性LOPD组的AA基因型频率比较,差异无统计学意义;男性LOPD组与男性健康对照组、女性LOPD组与女性健康对照组的AA基因型频率比较,差异无统计学意义.EOPD组的A等位基因频率(107/130,82.3%)高于健康对照组(87/132,65.9%),差异有统计学意义(X2=9.165,P=0.002);LOPD组分别与EOPD组、健康对照组的A等位基因频率比较,差异无统计学意义;男性EOPD组的A等位基因频率(60/70,85.7%)高于男性健康对照组(51/72,70.8%),差异有统计学意义(x2=4.606,P=0.032);女性EOPD组的A等位基因频率(47/60,78.3%)高于女性健康对照组(36/60,60.0%),差异有统计学意义(x2=4.728,P=0.030);男性LOPD组分别与男性EOPD组、男性健康对照组,女性LOPD组分别与女性EOPD组、女性健康对照组的A等位基因频率比较,差异均无统计学意义.结论 MAO-B的从基因型频率增高是EOPD组发病的危险因素;MAO-B的A等位基因频率增高是EOPD组、男性EOPD组及女性EOPD组发病的危险因素.     

单胺氧化酶B基因多态与早发帕金森病的相关性

Objective To investigate the association between polymorphisms in monoamine oxidase B (MAO-B)and early-onset Parkinson's disease(EOPD).Methods Polymerase chsin reactionrestriction fragment length polymorphism was used to identify the genotypes of polymorphisms in MAO-B in 65 patients in EOPD group(early-onset age<50 years),60 in late-onset Parkinson's disease(LOPD) group(late-onset age≥160 years)and 66 healthy controls(<50 years).Results The frequency of AA genotype was higher in EOPD groups(49/65,75.4%)than in healthy controls(34/66,51.5%),and the difference between them was statistically significant(x2=8.075,P=0.018).The frequency of AA genotype between EOPD group and LOPD group,between LOPD group and healthy controls had no statistical significance.The frequency of AA genotype between male in EOPD group and male healthy controls,between female in EOPD group and female healthy controls had no statistical significance.The frequencies of AA genotype between male in EOPD group and LOPD group,between female in EOPD group and in LOPD group had no statistical significance.The frequency of AA genotype between male in LOPD group and in healthy controls,between female in LOPD group and female healthy controls had no statistical significance.The frequency of A alleles was higher in EOPD group(107/130,82.3%)than in healthy controls(87/132,65.9%)and the difierence between them was statistical significant(x2=9.165,P=0.002).The frequency of A allele between EOPD group and LOPD group,between LOPD group and healthy controls had no statistical significance. The frequency of A allele was higher in male EOPD group (60/70,85.7%) than in male healthy controls(51/72,70. 8% ), the difference between them was statistically significant (X2 =4. 606, P=0. 032) ;the frequency of A alleles was higher in female in EOPD group (47/60,78. 3% ) than in female healthy controls(36/60,60. 0% ), the difference between them was statistical significance( x2 =4. 728, P = 0. 030). The frequency of A alleles between male EOPD group and male LOPD group, between female EOPD group and female LOPD group had no statistical significance. The frequency of A allele between male LOPD group and male healthy controls, between female LOPD group and female healthy controls had no statistical significance. Conclusions The AA genotype of MAO-B is the risk factor of EOPD. The A allele of MAO-B is a risk factor of EOPD group for both male and female.     

单胺氧化酶B基因多态与早发帕金森病的相关性

Objective To investigate the association between polymorphisms in monoamine oxidase B (MAO-B)and early-onset Parkinson's disease(EOPD).Methods Polymerase chsin reactionrestriction fragment length polymorphism was used to identify the genotypes of polymorphisms in MAO-B in 65 patients in EOPD group(early-onset age<50 years),60 in late-onset Parkinson's disease(LOPD) group(late-onset age≥160 years)and 66 healthy controls(<50 years).Results The frequency of AA genotype was higher in EOPD groups(49/65,75.4%)than in healthy controls(34/66,51.5%),and the difference between them was statistically significant(x2=8.075,P=0.018).The frequency of AA genotype between EOPD group and LOPD group,between LOPD group and healthy controls had no statistical significance.The frequency of AA genotype between male in EOPD group and male healthy controls,between female in EOPD group and female healthy controls had no statistical significance.The frequencies of AA genotype between male in EOPD group and LOPD group,between female in EOPD group and in LOPD group had no statistical significance.The frequency of AA genotype between male in LOPD group and in healthy controls,between female in LOPD group and female healthy controls had no statistical significance.The frequency of A alleles was higher in EOPD group(107/130,82.3%)than in healthy controls(87/132,65.9%)and the difierence between them was statistical significant(x2=9.165,P=0.002).The frequency of A allele between EOPD group and LOPD group,between LOPD group and healthy controls had no statistical significance. The frequency of A allele was higher in male EOPD group (60/70,85.7%) than in male healthy controls(51/72,70. 8% ), the difference between them was statistically significant (X2 =4. 606, P=0. 032) ;the frequency of A alleles was higher in female in EOPD group (47/60,78. 3% ) than in female healthy controls(36/60,60. 0% ), the difference between them was statistical significance( x2 =4. 728, P = 0. 030). The frequency of A alleles between male EOPD group and male LOPD group, between female EOPD group and female LOPD group had no statistical significance. The frequency of A allele between male LOPD group and male healthy controls, between female LOPD group and female healthy controls had no statistical significance. Conclusions The AA genotype of MAO-B is the risk factor of EOPD. The A allele of MAO-B is a risk factor of EOPD group for both male and female.