Association of synaptosomal-associated protein 25 (SNAP-25) gene polymorphism with temperament and character traits in women with fibromyalgia syndrome

Abstract Background: Synaptosomal-associated protein 25 (SNAP-25) may be contribute to the pathogenesis of fibromyalgia Syndrome (FMS) by affecting the release of neurotransmitters. Objectives: We aimed to investigate the relationship between the SNAP-25 gen (DdeI = rs1051312 and MnlI = rs3746544) polymorphism and the temperament and character traits. Methods: A total of 85 female patients diagnosed with FMS and 70 age-matched healthy female subjects were enrolled into the study. The Temperament and Character Inventory (TCI) were performed on all the patients. SNAP-25 gene polymorphism was determined in the patients group and controls group. Results: No significant difference between groups was found regarding the distribution of SNAP-25 MnlI polymorphism (p > 0.05), but it was seen that the frequency of TC genotype for DdeI gene was higher in the patients group (p < 0.05). Increased hazard avoidance was found in the patients group (p < 0.05). When TCI scores were assessed in terms of SNAP-25 gene polymorphism, no statistically significant relationship was detected between the TT, TG, GG genotypes for MnlI gen and TCI scores (p > 0.05). However, increased hazard avoidance was detected in patients with TC genotype for DdeI gene compared to patients without such genotype. Discussion: SNAP-25 might be an etiological factor in FMS pathogenesis and might affect personality traits of FMS patients by mediating neurotransmitter release.

No Association between the Polymorphism rs6943555 in the AUTS2 Gene and Personality Traits in Japanese University Students

OBJECTIVE: The autism susceptibility candidate 2 (AUTS2) gene has been implicated in multiple neurological disorders. Several recent studies have revealed that the polymorphism rs6943555 in the AUTS2 gene is broadly associated with human mental function and behavior. Therefore, in the present study we investigated whether the polymorphism rs6943555 is associated with human personality traits in Japanese university students. In addition, our previous study reported that the AUTS2 rs6943555-rs9886351 haplotype is associated with alcohol dependence. As a preliminary analysis, we also examined whether the AUTS2 haplotypes are related to personality traits. METHODS: After written informed consent had been obtained from the participants, two AUTS2 polymorphisms were analyzed, and personality was assessed using the Temperament and Character Inventory (TCI) in 190 university students. In addition, in order to exclude the influence of the results for students with mental health problems, we gave the Patient Health Questionnaire-9 (PHQ-9) to all subjects. RESULTS: In all the subjects, there was a main effect of the polymorphism rs6943555 genotype on reward dependence (p=0.038) and cooperativeness (p=0.031), although the significance was lost on Bonferroni correction. Similarly, on analysis that excluded the subjects with PHQ-9 scores≥10, no significant association with any TCI dimension score among the rs6943555 genotypes was seen. There was no effect of the rs6943555-rs9886351 haplotypes on the TCI dimension scores. CONCLUSION: This study suggests that the polymorphism AUTS2 rs6943555 is not associated with personality traits. Further large-scale studies with more subjects using other self-report questionnaires are needed.

Traços de personalidade de pessoas portadoras de hipertensão arterial crônica e doenças associadas / Personality traits of people with chronic hypertension and related diseases

O tratamento para hipertensão arterial crônica deve ser permanente e rigoroso para prevenir complicações, necessitando de alterações nos costumes e rotinas do indivíduo portador que pode ter seus aspectos emocionais também afetados. O objetivo deste trabalho foi compreender a relação entre os traços de personalidade e as características sócio-demográficas e clínicas de pessoas portadoras de hipertensão e doenças associadas. Participaram 33 indivíduos portadores de hipertensão arterial crônica e foram aplicados dois instrumentos para coleta de dados: Questionário de Caracterização e Inventário de Temperamento e Caráter de Cloninger. Através de análises estatísticas, os resultados indicaram que os indivíduos portadores de diabetes mellitus associada à hipertensão arterial são menos impulsivos e pessimistas e mais sociáveis, cooperativos e tolerantes quando comparados com indivíduos que possuem apenas diagnóstico de hipertensão.

Treatment for chronic hypertension should be permanent and strict to prevent complications, requiring changes in the habits and routines of the individual and which may have their emotional aspects also affected. The objective of this study was to understand the relationship between personality traits and socio-demographic and clinical characteristics of people with hypertension and related diseases. 33 individuals with chronic hypertension were included and two instruments for data collection were used: Characterization Questionnaire and Cloninger’s Temperament and Character Inventory. Through statistical analysis, the results indicated that patients with diabetes mellitus associated with hypertension are less impulsive and pessimistic and more sociable, cooperative and tolerant compared to indi-viduals with only hypertension diagnosis.

Temperamental Predictive Factors for Success in Korean Professional Baseball Players

OBJECTIVE: In this five-year cohort study, we hypothesize that factors of temperament and character in professional baseball players predict the speed of obtaining success and the quality of success as well as anxiety control. METHODS: Participants included 120 male rookie players from the Korea Baseball Organization (KBO) and 107 male non-players with no history of playing baseball. The personality/characters and state/trait anxieties of participants were assessed with the Temperament and Character Inventory (TCI) and Spielberg's State-Trait Anxiety Inventory-Y (STAI-Y). Over the duration of five years, all the players were subsequently classified into either a success group (major leaguers) or a non-success group (non-major leaguers), depending on their status in the professional baseball league in Korea. RESULTS: The players in the group of starters had higher novelty seeking (NS) scores than those of non-starters. The reward dependence (RD) scores of the success group were higher than those of the non-success group. The state anxiety scores in the starter group were negatively correlated with NS scores. The state and trait anxieties in the non-success group were positively correlated with RD scores. CONCLUSION: The results of this study suggest that predictive temperamental factors for success in baseball players include traits of novelty seeking and reward dependence.

Evaluation of Temperament and Character Features as Risk Factors for Depressive Symptoms in Patients with Restless Legs Syndrome

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) is a common sleep-related movement disorder that is frequently associated with psychological disturbances. Personality traits are of considerable importance with respect to coping with chronic illness and disease vulnerability. This study assessed the temperament and character traits of RLS patients using an approach that involves the psychobiological model of personality. METHODS: The personality features of 65 newly diagnosed and untreated RLS patients with no neurological or psychiatric diseases and 109 healthy controls were determined using the Temperament and Character Inventory and compared using covariance analyses. The International RLS Study Group Severity Scale was used to assess the severity of the RLS symptoms, and the Beck Depression Inventory was used to assess the presence and severity of depressive symptoms. RESULTS: RLS patients scored significantly higher than healthy controls on the temperament dimension of harm avoidance (HA, p=0.02) and significantly lower on self-directedness (SD, p=0.001). No significant difference was observed in terms of the temperament dimension of novelty seeking (p=0.435). HA scores were significantly correlated with the BDI score but not with the RLS severity or duration. CONCLUSIONS: High HA and low SD scores are the main characterizing personality features of RLS patients. These personality dimensions may be among the factors predisposing patients to development of the depressive symptoms that are frequently associated with RLS.

Application of the Seven-Factor-Model of Personality to an Italian Preschool Sample

OBJECTIVE: Advances in dimensional assessment of children in healthy and clinical populations has renewed interest in the study of temperament. Cloninger's Temperament and Character Inventory (TCI) has shown high reliability and internal consistency. Adult and adolescent versions have been translated into a number of languages and validated in cross-cultural studies worldwide. To date only one preschool-TCI-based study has been conducted in early infancy with teachers as observers. The present study is aimed to test an Italian Preschool version of the Temperament and Character Inventory (PsTCI). This is the first replication and the first validation study of TCI on preschoolers with parents as observers. METHODS: 395 preschool children, recruited from pediatric communities and day-care centres throughout Italy, participated in the study. Parents of each child enrolled in the study and completed a PsTCI about the child. Standard psychometric tests of reliability and validation were performed. RESULTS: Exploratory factor analyses demonstrated the presence of distinct domains for temperament and character. TCI dimensions had good internal consistency with Cronbach's alpha ranging values (|0.60|-|0.81|). Gender differences were found for Harm Avoidance (beta=-0.186; p< or =0.001) and Self-Directedness (beta=-0.216; p< or =0.01), and accounted for 5-35arm-38-702- of the observed variance. CONCLUSION: The present work suggests the psychological complexity of Cloninger's model and confirms its application in pre-school children from diverse environmental and cultural backgrounds. The results confirm that Cloninger's instrument for temperament and character evaluations can also be used with different observers and highlight the importance of considering cultural and demographic differences in the assessment of temperament and character in preschoolers.

Relationships between Chronotypes and Temperament and Character Dimensions in Healthy Young Adults

OBJECTIVES: Circadian rhythms have been known to have associations with psychiatric disorders and personality traits. The present study investigated the relationships between circadian typology and temperaments/characters in a non-clinical Korean population. METHODS: Two hundred six healthy Korean college students (male 109, female 97) participated in this study. The subjects completed the Composite Scale of Morningness for circadian typology and 140-item Temperament and Character Inventory-Revised-Short version (TCI-RS). RESULTS: Multivariate analyses of covariance showed a significant association between chronotypes and temperamental dimensions of the TCI-RS. Morning types were significantly associated with lower harm avoidance and higher persistence and self-directedness dimensions, compared to evening types and intermediate types. No interaction effects between sex and chronotypes were shown for temperamental dimensions. CONCLUSIONS: The present findings suggest that high persistence and self-directedness characters are related to morning types and high harm avoidance temperament is more related to evening types.

Right Amygdalar Laterobasal Subregional Differences in Healthy Adults with Different Novelty Seeking Tendencies

OBJECTIVES: Novelty seeking (NS) represents a dopaminergically modulated tendency toward frequent exploratory activity. Considering the reports showing the relationship between exploratory activity and amygdalar function and structure, and the fact that amygdala is one of the key structures that constitute the dopaminergic pathway in the brain, amygdala might be closely related to NS tendencies. Amygdalar subregional analysis method, which has the enhanced sensitivity compared to the volumteric approach would be appropriate in investigating the subtle differences of amygdalar structures among healthy individuals. The aim of the current study was to examine whether amygdalar subregional morphometric characteristics are associated with the NS tendencies in healthy adults using the amygdalar subregional analysis method. METHODS: Twenty-six healthy adults (12 males, 14 females ; mean age 29.8 +/- 6.2 years) were screened for eligibility. All subjects completed the Korean version of the Temperament and Character Inventory (TCI) and underwent high-resolution brain magnetic resonance imaging. Individuals were divided into 2 groups according to NS scores of the TCI. RESULTS: Individuals of the high NS group had significantly larger laterobasal subregions in right amygdala, after adjustment with the brain parenchymal volumes. Sensitivity analyses for each potential confounding factor such as age, education years and Hamilton Depression Rating Scale (HDRS) scores demonstrated consistent results. CONCLUSIONS: This study suggests that NS differences are associated with the laterobasal subregion of the amygdala.

Effects of Temperament and Character on the Specialty Interests of Medical Students

OBJECTIVES: In the previous studies, it has been suggested that temperament and character may affect specialty choice in medical students. The aim of this study is to investigate the effects of temperament and character on specialty interests in medical students. METHODS: A total 132 third-year medical students initially participated in this study. Among these participants, 128 students had filled out both demographic and Temperament and Character Inventory (TCI) questionnaires. Socio-demographic data, specialty interests and Cloninger's TCI scores were obtained. The specialty interests were categorized into surgical, medical and other departments. RESULTS: Among 128 students, 88 (68.7%), 29 (22.7%) and 22 (8.6%) students chose medical, surgical and other departments, respectively. Students choosing surgery departments showed lower Harm Avoidance scores (F = 4.39, df = 1, p = 0.04) and higher Self-Directedness scores (F = 4.30, df = 1, p = 0.04) than those who chose medical departments. There was no significant differences in Novelty Seeking, Reward dependence, Persistence, Cooperativeness, Self-Transcendence scores between groups. CONCLUSIONS: To the best of our knowledge, this is the first study that has demonstrated the relationship between TCI scores and specialty interests of medical students in Korea. The current study suggests that temperament and character influence specialty interests in medical students. These findings could have implications for medical education research and career counseling.

An Association Study of the Dopamine D2 Receptor Taq1A Polymorphism and Temperament in Korean Pathological Gamblers

OBJECTIVE: It has been suggested that the dopamine D2 receptor gene (DRD2) is associated with pathological gambling (PG). We investigated the association of the DRD2 Taq1A polymorphism and the temperament in PG using Cloninger's temperament and characteristic inventory (TCI). METHODS: 104 PG patients and 114 control subjects were recruited. Tests for DRD2 Taq1A polymorphism were conducted in both PG patients and controls. PG patients were requested to complete the TCI. RESULTS: There were no significant differences in frequencies of the genotype (chi2 = 0.77, p = 0.681), allele (chi2 = 0.52, p = 0.469), and allele (A1) carrier (chi2 = 0.15, p = 0.695) between the PG patients and the control group. When we compared the TCI profile in the PG patients according to genotypes, there were significant differences in harm-avoidance (HA, p = 0.033), and self-directedness (SD, p = 0.012) among genotypes. These difference were more evident between A1 allele carriers and non-carriers (HA, p = 0.009 and SD, p = 0.004). CONCLUSION: Present results suggest Taq1A polymorphism may not play an important role in the susceptibility to pathological gambling in our population. However, Taq1A polymorphism might be associated with some temperament in Korean PG patients.

The Relationships between Online Game Player Biogenetic Traits, Playing Time, and the Genre of the Game Being Played

OBJECTIVE: Psychobiological traits may be associated with excessive Internet use. This study assessed the relationships between biogenetic traits, the amount of time spent in online game playing, and the genre of the online game being played. METHODS: Five hundred sixty five students who enjoyed one of the four types of games included in this study were recruited. The types of games examined included role playing games (RPG), real-time strategy games (RTS), first person shooting games (FPS), and sports games. Behavioral patterns of game play, academic performance, and player biogenetic characteristics were assessed. RESULTS: The amount of time that the participants spent playing online games was significantly greater on weekends than on weekdays. On weekends, the types of games with the largest numbers of participants who played games for more than three hours were ranked as follows: RPG and FPS, RTS, and sports games. The Young's Internet Addiction Scale (YIAS)score for the RPG group was the highest among the groups of the four types of game players. The time that participants spent playing games on weekdays was negatively associated with academic performance, especially for the RPG and FPS groups. Compared with the other groups, the RPG and RTS groups had higher novelty seeking (NS) scores and self-directedness (SD) scores, respectively. Additionally, the sports game group had higher reward dependency scores than the other groups. CONCLUSION: These results suggest that RPGs may have specific factors that are attractive to latent game addicts with higher NS scores. Additionally, excessive playing of online games is related to impaired academic performance.

The Relationship between Harm Avoidance Temperament and Right Frontal and Left Parietal Lobes in Young Adults: A Cortical Thickness Analysis

OBJECTIVES: Increasing evidence suggests the presence of neurobiological bases for temperamental characteristics in humans. Brain correlates of harm avoidance(HA) have been most extensively studied using functional and structural brain imaging methods due to its potential link with anxiety and depressive disorders. To date, however, we are not aware of any reports that have examined the potential relationship between HA levels and regional cortical thickness. The aim of the current study is to examine the cortical thickness which is associated with HA temperament in healthy young subjects. METHODS: Twenty-eight young, healthy individuals(13 men and 15 women, mean age, 29.4 +/- 6.3 years) were screened for eligibility and administered the Korean version of the Cloninger's Temperament and Character Inventory and underwent high-resolution structural magnetic resonance imaging scanning. RESULTS: HA was associated with cortical thickness in the right superior frontal cortex and in the left parietal cortex, adjusted for age and sex and corrected for multiple comparisons using the permutation testing method. CONCLUSION: Individual temperamental differences in HA are associated with structural variations in specific areas of the brain. The fact that these brain regions are involved in top-down modulations of subcortical fear reactions adds functional significance to current findings.

Comparison of Clinical Features and Personality Dimensions between Patients with Major Depressive Disorder and Normal Control

OBJECTIVE: Personality dimension is considered as a risk factor of depression. This study was to compare aggression, impulsivity, hopelessness, and TCI (temperament and character dimensions) between patients with major depressive disorder (MDD) and normal controls. METHODS: A total of 56 MDD patients and the same number of normal controls who were matched for age, gender, and education were recruited. All subjects completed the following questionnaires; Aggression Questionnaire (AQ), Beck Hopelessness Scale (BHS), Barratt Impulsiveness Scale, 11th Version (BIS-11), and Temperament and Character Inventory (TCI). RESULTS: MDD patients were significantly higher scores in anger, hostility of AQ, BHS, motor impulsivity of BIS-11, and Harm Avoidances (HA) of TCI with all subscales of HA than normal controls, whereas novelty seeking 1 (NS1) (Exploratory of NS), Reward Dependence (RD) with RD3 (Attachment).RD4 (Dependence), Self-Directedness (SD) with most subscales of SD, Cooperativeness (CO), and ST3 (Spiritual Acceptance) showed lower scores than normal controls. Moreover, BHS and HA, BIS and NS showed moderate positive correlation in MDD patients, while BHS and SD, HA and SD were negatively correlated. CONCLUSION: The present study showed unique clinical features, especially personality dimensions of patients with MDD. Our results could be applicable to suggest treatment process and to predict one's prognosis for depression in that psychological properties are important for drug compliance and treatment response.

No Association between 5-HTTLPR and Harm Avoidance in Korean College Students

There have been numerous studies on the association between 5-HTTLPR (polymorphisms in the promoter region of the serotonin transporter gene) and anxietyrelated personality traits, with conflicting results. In this study, we administered Korean version of the Temperament and Character Inventory (K-TCI) to a sample of 158 Korean college students and genotyped for the 5-HTTLPR in order to compare the TCI dimensional scores including harm avoidance according to the 5-HTTLPR genotype and sex. We could not find the association between 5-HTTLPR and harm avoidance and other TCI measures. Considering known allele frequencies differences of 5-HTTLPR among different ethnic groups, further cross-cultural studies with a larger sample would be needed.

Serotonin Transporter-Linked Promoter Region Polymorphism and Personality Traits in a Korean Female Population

OBJECTIVES: Findings from behavioral genetics which demonstrate the high heritability of personality traits have stimulated the search for the specific genes underlying personality. A large number of association studies have investigated a correlation between serotonin transporter-linked promoter region(5-HTTLPR) polymorphism and personality traits but the results have been inconsistent. So, the aim of this study is to investigate in a large sample with homogenous background about ethnicity, gender, occupation, and age. METHODS: The participants included 247 healthy Korean female adults(mean age=23.12, SD=3.22)with no history of psychiatric disorders and other physical illnesses. Genomic DNA was extracted from peripheral blood, and genotyping was performed by PCR. Personality assessment was done with the Temperament and Character Inventory(TCI). RESULTS: Genotype Frequencies are l/l 3.6%, l/s 32.8% and s/s 63.6%(l allele: 20%, s allele: 80%). This low frequency of the l allele and l/l genotype was different from Caucasian results. No significant association was observed between 5-HTTLPR polymorphism and personality traits in a Korean female population. CONCLUSIONS: This study investigated the association between 5-HTTLPR polymorphism and personality traits in Korean female subjects, a large sample with homogeneous background about ethnicity, gender, occupation, and age. No significant association was observed between 5-HTTLPR polymorphism and personality traits in a Korean female population.

Lack of Association between Polymorphisms of the Dopamine Receptor D4 and Dopamine Transporter Genes and Personality Traits in a Korean Population

Human personality traits have a considerable genetic component. Cloninger et al. were the first to postulate that certain personality traits, such as novelty seeking, are related to the dopamine neurotransmitter system. In this study, we investigated the associations between dopamine receptor D4 (DRD4) exon III and dopamine transporter (DAT1) polymorphisms and personality traits. The DRD4 and DAT1 gene polymorphisms were genotyped in 214 healthy Korean subjects, whose personality traits were assessed with the Temperament and Character Inventory (TCI). There were no significant differences between scores of TCI temperament dimensions (novelty seeking, harm avoidance, reward dependence, and persistence) and DRD4 gene polymorphism. The DAT1 gene polymorphisms also showed no significant association with any of the temperament subscales of the TCI. These data suggest that DRD4 and DAT1 gene polymorphism may not associated with personality traits in a Korean population.

Temperament and Character in Euthymic Bipolar I Patients with or without Psychotic Features / 신경정신의학

OBJECTIVES: The aim of this study was to exam whether personality, i.e. temperament and character, has an association with a previous presence of psychotic features in euthymic bipolar I disorder. METHODS: We recruited 25 psychotic patients with bipolar I disorder, 23 non-psychotic bipolar I patients and 48 normal controls. All subjects were asked to perform Temperament and Character Inventory (TCI). Euthymic state was defined in bipolar patients by scores of below 10 on the Hamilton Depression Rating Scale (HDRS) and on the Young Manic Rating Scale (YMRS). RESULTS: Psychotic bipolar patients, compared to normal controls, showed higher harm avoidance (HA) and self-transcendence (ST). In addition, HA in psychotic bipolar patients was higher than that in non-psychotic bipolar patients. However, no significant differences on TCI were demonstrated between non-psychotic patients and normal controls. CONCLUSION: There are significant discrepancies in personality between psychotic and non-psychotic bipolar patients on HA and ST. These findings are consistent with the hypothesis of a continuum between bipolar disorder with psychotic features and psychotic disorders.

Polymorphisms in 5-HT1Dbeta Receptor Gene and Personality Traits in a Korean Population / 신경정신의학

OBJECTIVES: Recently, there has been a growing enthusiasm in biological approach to personality; the identification of genes responsible for particular personality traits. The aim of this study was to investigate the association between the 5-HT1Dbeta G861C polymorphism and personality traits. METHODS: We recruited 218 normal subjects. The Korean version of the Temperament and Character Inventory (TCI) was used to assess personality traits. From blood samples taken from the subjects, DNA was isolated using standard techniques and the HT1Dbeta G861C polymorphism was genotyped by means of polymerase chain reaction and Homogeneous MassEXTEND method. We classified the subject into the GG, CG, and GG groups according to their genotypes. The differences in the temperament factors of the TCI between homozygote group (GG+CC genotype) and heterozygote group (CG genotype) were tested. RESULTS: The heterozygote group had significantly lower Harm avoidance (HA) scores and higher Self-directedness scores (SD) than the homozygote group. CONCLUSION: In conclusion, we found some associations between the 5-HT1Dbeta G861C polymorphism and the personality dimension HA and SD in a normal population.

An Association Study of the Brain-Derived Neurotrophic Factor Genes Polymorphisms and Personality Traits

BACKGROUND: Brain-derived neurotrophic factor(BDNF) genes are thought to be important factors in some personality traits. The goal of this study was to determine the role of these genes in personality traits. METHOD: The participants included 170 healthy adults with no history of psychiatric disorders and other physical illnesses for the last 6 months. All participants were tested by the Temperament and Character Inventory (TCI). BDNF Val64Met gene polymorphisms were analyzed with PCR(Polymerase Chain Reaction). Differences on TCI dimensions and sub-scales among groups were examined with ANOVA. RESULT: There was a significant correlation between BDNF Val64Met and Persistence(PS)(p=0.036) in female subjects, but none with the other TCI dimensions. A post-hoc comparison revealed significant a difference between Val/Val and Met/Met (p=0.031). CONCLUSION: Our study suggests that the BDNF Val64Met gene polymorphism is associated with persistence in Korean female subjects, but the small number of subjects limits generalization of our results. Further studies with a larger number of homogenous subjects are needed to confirm whether the BDNF gene is related to personality traits.

Temperament and Charcater Dimensions of Posttraumatic Stress Disorder in Burn Patients

OBJECTIVE: The aim of this study was to evaluate the temperament and character profiles of the patients with posttraumatic stress disorder(PTSD) after burn injury. METHODS: The study subjects consisted of 23 PTSD patients after burn injury, 24 patients not being diagnosed as PTSD after burn injury(non-PTSD) and 53 healthy controls. The assessment of PTSD was performed using clinician administered PTSD scale. All participants were instructed to complete the Temperament and Character Inventory(TCI), the Beck Depression Inventory and the State and Trait Anxiety Inventory of Spielberger. RESULTS: The PTSD group after burn injury, compared with the non-PTSD group and the normal controls, had the higher novelty seeking and harm avoidance scores. But there were no differences in other dimensions in the TCI among the three groups. CONCLUSION: The results of this study suggest that the PTSD group after burn injury showed the specific properties of temperament and character compared with the non-PTSD group and the normal group.