多巴胺D4受体基因和5-羟色胺转运体基因与注意缺陷多动障碍及其相关症状的关联分析

目的 探讨多巴胺D4受体(DRD4)基因和5-羟色胺转运体(5-HTT)基因与注意缺陷多动障碍(ADHD)及其相关症状的关系.方法利用Achenbach父母用儿童行为调查表评定139例ADHD患儿(患者组)的临床症状;采用聚合酶链反应、聚丙烯酰胺凝胶电泳结合银染技术,检测患者组和115名正常儿童(对照组)的基因型和等位基因频率.结果 (1)患者组与对照组间DRD4和5-HTT基因的基因型及等位基因频率分布的差异无统计学意义(P>0.05).(2)5-HTT基因的S/S基因型个体的社会退缩[(4.4±3.0)分]、躯体主诉[(3.6±2.7)分]得分高于S/L+L/L基因型个体[(3.3±2.6)分和(2.6±2.6)分],差异有统计学意义(P<0.05).(3)在非携带DRD4基因3等位基因个体中,S/L+L/L基因型的注意问题[(10.4±3.1)分]和社交问题[(7.2±3.7)分]得分高于S/S基因型个体[分别为(8.7±3.1)分和(5.3±2.3)分],差异有统计学意义(P<0.05).结论 DRD4基因和5-HTT基因与ADHD可能无关联;但5-HTT基因与ADHD的某些内化性症状可能存在关联;对ADHD的某些症状(注意问题和社交问题),DRD4基因与5-HTT可能存在相互协同作用.     

Interaction between serotonin transporter promoter and dopamine receptor D4 polymorphisms on decision making

Appropriate decision making is an important brain function to maintain our lives. The Iowa gambling task (IGT) is a tool for decision making under ambiguity. The aims of this study were to evaluate the influence of serotonin transporter linked polymorphic region (5-HTTLPR) and dopamine receptor D4 (DRD4) polymorphisms and their interaction on IGT performance. One hundred fifty-nine normal subjects were involved in this study. All subjects performed the IGT and were genotyped for the triallelic 5-HTTLPR and DRD4 48 bp uVNTR polymorphisms.After controlling for gender, age, and impulsiveness, there were no main effects of 5-HTTLPR and DRD4 gene polymorphisms on total IGT score. However, there was a significant effect on the interaction between 5-HTTLPR and DRD4 on total IGT score. In the presence of the 5-HTTLPR S′S′ (SS + SL_G + L_GL_G), subjects with the DRD4 2R+ (2 repeat carrier) had higher total IGT score compared to those with the DRD4 2R–. In contrast, in the absence of the 5-HTTLPR S′S′, subjects with the DRD4 2R– had higher total IGT score than those with the DRD4 2R+. When we divided IGT scores into the first and second half of trials, the 5-HTTLPR × DRD4 interaction effects were stronger in the second half block (decision under risk) than in the first half block (decision under ambiguity). In conclusion, the DRD4 genotypes might influence decision-making performance differently according to the background genotypes of 5-HTTLPR.     

Interaction between the dopamine D4 receptor and the serotonin transporter promoter polymorphisms in alcohol and tobacco use among 15-year-olds

Early onset of alcohol and tobacco use during adolescence increases the risk for establishing a substance use disorder in adulthood. Both alcohol and nicotine stimulate the dopamine (DA) and the serotonin (5-HT) systems. The DA system has been implicated in the mediation of the rewarding effects of self-administered drugs of abuse. A possible role of an interaction between these neurotransmitter systems in substance use behavior has been suggested but is as yet unknown. The present study was designed to examine the influence of the DA D4 receptor (DRD4) and the serotonin transporter (5-HTT) genotype and their interaction on adolescent alcohol and tobacco experimentation. Participants were from a longitudinal study of a birth cohort consisting initially of 384 children from a high-risk community sample. At the age of 15 years, adolescents completed a self-report questionnaire measuring tobacco and alcohol consumption. DNA was taken from 305 participants (146 boys, 159 girls) and genotyped for the DRD4 exon III and the 5-HTTLPR polymorphisms. The DRD4 7-repeat allele was associated with greater smoking and drinking involvement in boys. In girls, a significant DRD4 × 5-HTT interaction was detected. Girls without the DRD4 7-repeat allele and who were homozygous for the long allele of 5-HTTLPR displayed the highest smoking and drinking activity. The genetic and potential molecular background underlying adolescent vulnerability to substance abuse is discussed.     

Anxiety- and novelty seeking-related personality traits and serotonin transporter gene polymorphisms

The affection of human personality by the promoter and the intron 2 polymorphism in the serotonin transporter gene (SERT) is inconsistently reported. We aimed to clarify this situation by gender-specific haplotype-phenotype association. 98 women and 97 men completed the personality inventories NEO-PI-R and TPQ. The subjects were genotyped for the two SERT polymorphisms and the haplotypes were calculated. The short (S) and long (L) promoter alleles and the 12 and 10 repeat intron 2 alleles formed the haplotypes S 12, S 10, L 12 and L 10. In men, scores in the anxiety-related dimensions were higher in S 12 than in L 12 carriers. Opposite in direction, scores tended to be lower in S 10 than in L 10 carriers. In the novelty seeking-related dimensions, scores were higher in S 10 than in S 12 carriers. No association was observed in women. In conclusion, anxiety- and novelty seeking-related personality dimensions are differentially associated with different SERT haplotypes; the consistent restriction to men suggests common androgen regulation. Opposite trends with haplotypes including the same promoter alleles suggest contribution of group stratification to earlier inconsistent findings and call to further differentiate the molecular function and clinical implications of the SERT promoter polymorphism.     

Association of the serotonin transporter and receptor gene polymorphisms in neuropsychiatric symptoms in Alzheimer disease

BACKGROUND: Serotonin has been linked to neuropsychiatric symptoms in Alzheimer disease, mainly agitation/aggression, depression, and psychosis. Neuropsychiatric symptoms have been associated with polymorphisms of the promoter region (5-HTTPR ) and intron 2 of the serotonin transporter gene (5-HTTVNTR) or the 5-HT2A and 5-HT2C receptor genes in some but not all studies. OBJECTIVE: To examine the association of the serotonin promoter, transporter, and receptor genes with neuropsychiatric symptoms in patients with Alzheimer disease. METHODS: The sample included 96 patients with Alzheimer disease from the outpatient clinic of the University of California Los Angeles Alzheimer's Disease Research Center, Los Angeles. The Neuropsychiatric Inventory was used to measure neuropsychiatric symptoms, and blood samples were available for genetic analysis. Based on the literature, we hypothesized that the 5-HT2A and 5-HT2C receptor polymorphisms would be associated with agitation/aggression and psychosis and the 5-HTTPR or 5-HTTVNTR polymorphisms, with agitation/aggression or depression and anxiety. One-way analyses of variance were performed with age, ethnicity, sex, or education as covariates. RESULTS: The 102T genotype of the 5-HT2A receptor was significantly associated with delusions (P =.045) and agitation/aggression (P =.002). We did not replicate previous associations of the 5-HT2C receptor polymorphism with psychosis or of the 5-HTTPR polymorphism with agitation/aggression, psychosis, or depression. We did not find any associations with the 5-HTTVNTR polymorphism and agitation/aggression, depression, or anxiety. CONCLUSIONS: The 5-HT2A receptor polymorphism may contribute to the expression of psychosis and agitation/aggression in patients with Alzheimer disease. Absence of other positive associations may be due to the relatively small sample size and/or potentially small effect size of the polymorphisms and requires further study.     

广泛性焦虑障碍与5-羟色胺转运体基因多态性的相关研究

目的　探讨广泛性焦虑障碍与 5 羟色胺转运体 (5 HTT)基因启动子区和内含子 2区两种多态性的相关性。方法　运用聚合酶链反应技术检测 4 7例广泛性焦虑障碍患者 (患者组 )和 90名健康对照者 (对照组 )两种基因多态性的分布频率。结果　患者组启动子区多态性 (5 HTTLPR)的short/short(SS)基因型和short(S)等位基因频率分别为 72 %和 83% ,对照组SS基因型和S等位基因频率分别为 4 9%和 71% ,两组间的差异有显著性 (P <0 0 5 )。内含子 2区数目可变的顺向重复多态性各基因型 (12 / 12 ,12 / 10 ,10 / 10 )频率在患者组中分别为 72 % ,2 6 % ,2 % ,在对照组中分别为 78% ,2 1% ,1% ,两组间的差异无显著性 (P >0 0 5 ) ;等位基因频率比较的差异亦无显著性 (P >0 0 5 )。结论　 5 HTTLPR的SS基因型可能是广泛性焦虑障碍的易感基因之一。     

Association analysis of serotonin transporter promoter gene polymorphism with ADHD and related symptomatology

Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood behavioral disorders. Genetic factors contribute to the underlying liability to develop attention deficit hyperactivity disorder. Several investigations have reported associations between ADHD and serotonin transporter promoter polymorphisms, but the results have been inconsistent. The present study did not find significant association between ADHD and serotonin transporter promoter polymorphisms, but did find an effect of serotonin transporter promoter polymorphisms on some ADHD symptomatology. Patients homozygous for the short allele showed more Withdrawn or Somatic complaint scores than subjects with the long allele.     

Association study of catechol-O-methyltransferase gene and dopamine D4 receptor gene polymorphisms and personality traits in healthy young chinese females

Human personality traits, which are substantially heritable, may be modulated by monoamine neurotransmitters. It has been demonstrated that the catechol-O-methyltransferase (COMT) Val158Met genetic polymorphism, a functional polymorphism that may affect monoamine metabolism, is possibly associated with specific personality traits. In addition, a polymorphism in the dopamine D4 receptor (DRD4) gene exon 3 has been associated in some, but not all, studies with the novelty seeking personality trait, as evaluated by the Tridimensional Personality Questionnaire (TPQ). In this study, associations between these two polymorphisms and TPQ personality traits were investigated in a sample population of 120 healthy young Chinese females. The results of this analysis reveal that the COMT Val158Met polymorphism was significantly associated with novelty seeking (p = 0.017) and reward dependence scores (p = 0.015) in our sample. However, no significant differences were demonstrated comparing TPQ-specific scores for subjects bearing different DRD4 genotypes. The present study suggests that the functional COMT Val158Met genetic polymorphism contributes to individual differences in the personality traits novelty seeking and reward dependence. Similar to the results of a recent meta-analytic review, however, no association was demonstrated between this DRD4 polymorphism and novelty seeking in our young Chinese female sample population.     

Association of dopamine and opioid receptor genetic polymorphisms with response to methadone maintenance treatment

BACKGROUND: Genetic variations of the dopamine and opioid receptors could influence the response to methadone maintenance treatment (MMT). METHODS: We included 238 MMT patients according to their response to treatment and methadone dosing, along with 217 subjects without substance dependence. All were genotyped for polymorphisms of the dopamine D(1), D(2), micro-opioid and delta-opioid receptor genes. Results: The polymorphisms of the micro-opioid (118A>G), delta-opioid (921T>C), dopamine D(1) (DdeI) and D(2) (TaqI A) receptor genes were not associated with response to MMT and methadone dosing, whereas an association was found with the dopamine D(2) receptor (DRD2) 957C>T polymorphism. The 957CC carriers were more frequently non-responders to treatment (OR=2.4; p=0.02) and presented a fourfold shorter period of negative urine screening (p=0.02). No significant differences in allele frequencies were observed between the MMT patients and the control group, suggesting no association of the analyzed polymorphisms with opioid dependence. CONCLUSIONS: These results suggest that DRD2 genotype may contribute to the understanding of the interindividual variability to the response to MMT.     

Association between tridimensional personality questionnaire (TPQ) traits and three functional polymorphisms: dopamine receptor D4 (DRD4), serotonin transporter promoter region (5-HTTLPR) and catechol O-methyltransferase (COMT)

Dopamine D4 receptor (DRD4), serotonin transporter promoter regulatory region (5-HTTLPR) and catechol O-methyltransferase (COMT) polymorphisms were examined for association with TPQ personality factors in 455 subjects. Significant interactions were observed by multivariate analysis, (COMT x 5-HTTLPR: Hotelling's Trace = 2.3, P = 0.02) and by subsequent univariate 3-way ANOVA when Novelty Seeking (NS) was the dependent variable: 5-HTTLPR x D4DR (F = 6.18, P = 0.03) and COMT x 5-HTTLPR (F = 4.42, P = 0.03). In the absence of the short 5-HTTLPR allele and in the presence of the high enzyme activity COMT val/val genotype, NS scores are higher in the presence of the DRD4 seven-repeat allele. The effect of these three polymorphisms on NS was also examined using a within-families design. Siblings who shared identical genotype groups for all three polymorphisms (COMT, DRD4 and 5-HTTLPR) had significantly correlated NS scores (intraclass coefficient = 0.39, F = 2.26, P = 0.008, n = 49) whereas sibs with dissimilar genotypes in at least one polymorphism showed no significant correlation for NS scores (intraclass coefficient = 0.177, F = 1.43, P = 0.09, n = 110). Similar interactions were also observed between these three polymorphisms and Novelty Seeking when the 150 independently recruited and non-related subjects were analyzed. The current results are consistent with two earlier reports in which we demonstrated an interaction between the 5-HTTLPR and DRD4 polymorphisms in 2-week-old neonates, in the same children assessed again at 2 months of age and in adults. Molecular Psychiatry (2000) 5, 96-100.     

MST-4基因启动子多态位点与AD的相关性研究

目的 探讨MST-4(丝/苏氨酸蛋白激酶-4)基因启动子区多态性、载脂蛋白E(ApoE)基因多态性和阿尔茨海默病(AD)的相关性.方法 通过使用TaqMan-PCR法检测单核苷酸多态性(SNP)方法,在377例日本人AD患者,包括324例迟发型AD(LOAD)与53例早发型AD(EOAD)和379例非痴呆对照组中观察MST4基因启动子rs2748729(-3507A/G)及APOE基因的多态性分布,并分析与AD的相关性.结果 (1)MST4基因启动子rs2748729上G/G纯合子频率在AD中明显低于对照组(0.28比0.35,P值为0.038);同样趋势见于LOAD,EOAD与对照组,但P值均>0.05;(2)进一步在非APOE4携带者中比较发现rs2748729上G/G纯合子频率在AD中亦低于对照组(0.27比0.35),但P值为0.078;(3)进一步性别分层分析发现女性群体中rs2748729上G/G纯合子频率在AD与对照组中无显著性差异.结论 MST-4基因启动子rs2748729多态位点与AD存在微弱相关性,G/G纯合子具有一点的保护作用,但这种相关性不表现在女性人群中,需在大样本、多中心人群中进一步去阐明.     

Association between dopamine D3 receptor gene polymorphisms and schizophrenia in an isolate population

There are several lines of evidence implicating the dopamine D3 receptor in the pathophysiology of schizophrenia. The Ser9Gly polymorphism of the dopamine D3 receptor gene (DRD3) has been the most extensively investigated DRD3 variant in connection with the disease but results have been inconclusive. Recent reports indicate that the Ser9Gly polymorphism is in linkage disequilibrium with other markers, but association studies between DRD3 haplotypes and schizophrenia have had mixed results. Genetic heterogeneity may be one of the causes of contradicting results. In order to clarify the role of DRD3 alterations in the aetiology of disease, we have investigated three D3 genetic variants (Ser9Gly, -205-G/A, -7685-G/C) in a sample of patients with schizophrenia or schizoaffective disorder (N=118) and controls (N=162) recruited from a human isolate from Navarra (Northern Spain) of Basque origin. Although no association was found between the Ser9Gly or the -205-A/G polymorphisms and disease, an excess of allele -7685-C was observed in patients (p=0.002 after correction for multiple analyses). Haplotype analysis shows the three markers to be in strong linkage disequilibrium (p<0.0001) and strongly associated with disease (p<1x 10(-5)). These results may suggest that these polymorphisms exert a combined or synergistic effect on susceptibility to schizophrenia, or are in linkage with an unknown causative factor. However, further replication in independent samples is required.     

Association between dopamine D4 receptor (DRD4) gene polymorphisms and novelty-elicited auditory event-related potentials in preschool children

We investigated associations of the exon III repeat and the -521 C/T polymorphisms of the DRD4 gene with novelty-elicited auditory ERP components and behavioral resistance to distraction in 57 healthy, typically developing 6-year-old children. Dopamine-related gene polymorphisms have previously been linked to processes directing focused attention. We did not find associations between the 7-repeat allele or the T.7 haplotype and the early ERP responses suggesting that DRD4 polymorphisms did not affect the detection of novelty. However, the same polymorphisms affected the late negative components (LN1 and LN2). Late negativities elicited by deviant and novel sounds have been regarded as reflecting reorientation after distraction or additional processing of new information. Children carrying the T.7 haplotype had significantly smaller LN1 and LN2 amplitudes. The presence of the T.7 haplotype also significantly enhanced behavioral resistance to distraction. We suggest that less distraction in T.7 carriers led to less reorienting activity (reflected by the LN components). We also speculate that activation of less sensitive and fewer D4 receptors (as with the T.7 haplotype) is less effective in modulating GABAergic inhibitory signaling, which in turn is reflected in smaller LN amplitudes.     

Association study of dopamine D2, D3 receptor gene polymorphisms with motor fluctuations in PD.

The authors investigated the association between dopamine receptor D2, D3 gene polymorphisms, and the risk of developing motor fluctuations in PD. DRD3 BalI and MspI polymorphisms were not associated with risk of developing motor fluctuations. However, the genotypic distribution of DRD2 TaqIA polymorphism was significantly different in motor fluctuators and nonmotor fluctuators. These findings suggest that DRD2 TaqIA polymorphism may be associated with an increased risk for developing motor fluctuations in PD.     

多巴胺D2受体基因rs1800497多态性与精神分裂症的关联分析

目的 探讨中国汉族人群多巴胺D2受体（DRD2）基因rs1800497多态性与精神分裂症发病的关系及其与性别的关联性.方法 采用TaqMan法检测200例精神分裂症患者（患者组）和219名健康对照（对照组）DRD2基因rs1800497单核苷酸多态性（SNP）,并对等位基因、基因型频率进行比较.结果 患者组与对照组rs1800497等位基因分布和基因型分布差异均无统计学意义（P＞0.05）.患者组或对照组不同性别rs1800497等位基因分布和基因型分布差异均无统计学意义（P＞0.05）.男性患者组与对照组相比或女性患者组与对照组相比,rs1800497等位基因分布和基因型分布差异均无统计学意义（P＞0.05）.结论 中国汉族人群DRD2 rs1800497位点可能不是精神分裂症的易感位点.