5-羟色胺2A受体基因-1438A/G多态性与抑郁症的关联研究

目的探讨中国汉族人群中抑郁症患者与5-羟色胺2A(5-HT2A)受体基因-1438A/G多态性之间的关系。方法采用高温连接酶检测反应法,检测254例抑郁症患者和231例正常对照者的5-HT2A受体基因-1438A/G多态性的基因型和等位基因分布。结果(1)5-HT2A受体基因-1438A/G多态性的基因型和等位基因频率在患者组和对照组的分布差异无统计学意义(P>0.05)。(2)患者组-1438A/G多态性的三种基因型之间的汉密尔顿抑郁量表总分和各因子分的差异无统计学意义(P>0.05)。(3)-1438A/G多态性基因型及等位基因在性别和有无精神病疾病家族史之间无显著差异(P>0.05)。结论在中国汉族人群中未发现5-HT2A受体基因-1438A/G多态性与抑郁症存在关联。     

自杀未遂与5-HT2A受体基因A-1438G多态性的关联研究

目的探讨5-HT2A受体基因A-1438G多态性与自杀未遂之间的关系.方法以145名自杀未遂者为研究对象,190名正常人为对照.采用聚合酶链式反应(PCR)扩增及内切酶酶切技术测定所研究对象的基因型和等位基因.结果男性自杀未遂与5-HT2A受体基因A-1438G多态性的基因型A1/A1关联.结论5-HT2A受体基因A-1438G多态性与男性的自杀易感性相关.     

精神分裂症攻击行为与5-HT2A受体基因多态性的关联研究

目的探讨精神分裂症患者的攻击行为与5-HT2A受体基因T102C和A1438G多态性的相关性。方法采用《修订版外显攻击行为量表》(MOAS)对精神分裂症患者进行评定,MAOS评分≥5分为研究组,MOAS≤4为对照组。并采用聚合酶链反应(PCR)和限制性片断长度多态性(RFLP)技术,检测103例伴发攻击行为精神分裂症(研究组)和99例非攻击行为精神分裂症患者(对照组)5-HT2A基因型,并分别比较两组5-HT2A受体基因T102C位点多态性和A1438G位点多态性差异。结果研究组和对照组T102C位点多态性的等位基因频率和基因型频率分布统计学均具有显著性差异(P0.01),研究组基因型T/T频率和等位基因T频率均高于对照组(χ2=10.126,P=0.006),(χ2=8.176,P=0.004);A1438G位点多态性基因型频率分布差异无统计学意义(P0.05),而等位基因频率分布差异具有统计学意义(P0.05),研究组等位基因A频率高于对照组。结论 5-HT2A受体基因T102C位点和A1438G位点的多态性与精神分裂症的攻击行为均具有相关性,其等位基因T和A可能增加患者攻击行为的风险。     

5-羟色胺2A受体基因多态与海洛因成瘾及渴求程度的关联分析

目的探讨5-HT2A-1438A／G基因多态与海洛因成瘾及线索诱发海洛因渴求程度的关系。方法采 用PCR-RFLP技术对380例海洛因依赖者(依赖组)和275名健康人(对照组)的5-HT2A-1438A／G基因多态进行检 测,并对依赖组行线索诱发海洛因渴求实验。比较依赖组和对照组的5-HT2A-1438A／G多态基因型及等位基因频 率,分析依赖组不同基因型与线索诱发海洛因渴求程度和主观戒断反应的关系。结果 (1)依赖组与对照组的5- HT2A-1438A／G的基因型和等位基因频率均无显著性差异(P>0．05)。(2)依赖组中,5-HT2A-1438A／G的3种多态 基因型诱发渴求和主观戒断反应的差异有统计学意义(P<0．05),G／G基因型诱发渴求和主观戒断反应均小于A／ A(P=0．024,P=0．009)和A／G(P=0．018,P=0．011)基因型。结论未发现5-HT2A-1438A／G基因多态与海洛 因成瘾有关,但该基因多态性与线索诱发海洛因的渴求程度有关,A+(A／A和A／G)携带者线索诱发海洛因的渴求 程度和主观戒断反应明显高于A-(G／G)携带者。     

强迫症与5-羟色胺受体基因的关联研究

目的探讨北方汉族人群中5-HT2A、5-HT2C、5-HT1Dβ受体基因与强迫症(OCD)的相关性。方法采用聚合酶链反应-限制性片段长度多态技术测定225例强迫症患者和175名正常对照的5-HT2A-1438G/A、5-HT2CCys23Ser、5-HT1DβG861C多态性的基因型,根据强迫症的共病情况、发病年龄、临床表现将OCD划分亚型进行与5-羟色胺受体基因多态性的关联分析。结果OCD组5-HT1Dβ等位基因861C频率与对照组有显著性差异(2=4.39,P=0.04),而5-HT2A、5-HT2C2个位点基因型和等位基因及5-HT1Dβ基因型的频率与对照组之间差异无显著性(P>0.05);OCD共病其他精神障碍组5-HT1Dβ基因型与等位基因频率与对照组有显著性差异(2=7.12,P=0.03;2=7.56,P=0.006),而无共病组3个位点基因型与等位基因频率与对照组无显著性差异(P>0.05);早发OCD组5-HT2A基因型和等位基因频率与对照组有显著性差异(Х2=8.97,P=0.01;Х2=8.05,P=0.005);强迫思维合并强迫行为的患者5-HT2A基因型与等位基因频率与对照组有显著性差异(Х2=9.15,P=0.01;Х2=8.38,P=0.004)。结论5-HT2A-1438G/A多态性与强迫思维合并强迫行为的OCD亚型及早发型OCD的发病存在关联;5-HT1DβG861C多态性与共病其他精神障碍的OCD相关,有/无共病强迫症可能有不同的发病机制。     

同胞精神分裂症与5-羟色胺2A受体基因的关联分析

目的 探讨慢性精神分裂症患者的受累同胞和散发性精神分裂症与5-羟色胺2A受体基因(5-HT2A)T102C多态性的关联。方法 先用严格的纳入标准收集共患慢性精神分裂症的同胞60对(120例)和散发性精神分裂症120例,分别与正常同胞60对(120名)和120名正常人对照,采用聚合酶链反应(PCR)扩增及MspI内切酶酶切技术,检测各组的5-HT2A受体基因的基因型和等位基因的频率分布。结果 60对共患慢性精神分裂症的受累同胞组5-HT2A受体基因A1／A1基因型频率显著高于正常同胞组(X2=5.58,P<0.05),经配对比较,患者同胞组共有A1／A1基因型也显著多于正常同胞组(X2=3.94,P<0.05),而散发性精神分裂症与正常人对照组各基因型和等位基因的构成差异均无显著性意义。结论 共患慢性精神分裂症的同胞与5-HT2A受体基因A1／A1型关联,A1／A1纯合子易患精神分裂症,散发性精神分裂症可能与5-HT2A受体基因无关联。     

5-羟色胺2A受体基因多态性与抑郁症的关联研究

目的探讨5-羟色胺2A（5-HT2A）受体基因T102C和A-1438G多态性与抑郁症的关系。方法采用聚合酶链式反应（PCR）和限制性片断长度多态性（RFLP）技术检测123例抑郁症患者和122名健康对照的T102C和A-1438G基因多态性分布,病例-对照关联分析法分析两组间基因型频率和等位基因频率的差异。结果5-HT2A基因T102C多态性等位基因频率和A-1438G等位基因频率在患者组和对照组间的分布均有显著性差异（P〈0．05）,患者组C102等位基因频率（30．1％）明显低于对照组（41．0％）,在分层分析中,男性患者组中频率（26．2％）明显低于男性对照组（50．0oA）;患者组A-1438等位基因型频率（69．1％）明显高于对照组（56．6％）,A-1438等位基因在女性患者组中频率（69．1％）明显高于女性对照组（55．2％）。患者组中TT／AA（T102T／A-1438A）基因型组合频率（43．9％）明显高于对照组（20．5％）。结论5-HT2A基因T102C和A-1438G多态性可能与抑郁症的发病有关,其中C102等位基因可能是男性罹患抑郁症的保护因子,A-1438等位基因可能是抑郁症特别是女性抑郁症患病的危险因子,T102T和A—1438A基因型同时出现可能是抑郁症发病的重要危险因素。     

5-羟色胺2A受体基因多态性与精神分裂症患者迟发性运动障碍的关联分析

目的　探讨5- 羟色胺2A( 5- HT2A)受体基因A 1 4 38G、T1 0 2C多态性与精神分裂症伴迟发性运动障碍(TD)的相关性。方法　先用异常不自主运动量表(AIMS)评定精神分裂症男性患者有无TD及其严重程度,有4 2例符合TD(AIMS总分≥3分)者和51例与TD组严格相匹配的非TD者入组,采用简明精神病评定量表(BPRS)评定精神症状,应用聚合酶链反应 限制性片段长度多态性方法分析5 HT2A受体基因的A 1 4 38G、T1 0 2C多态性位点的多态性。结果　①5- HT2A受体基因A 1 4 38G和T1 0 2C两位点多态性呈完全连锁不平衡,TD组与非TD组的两多态性位点的基因型总体分布无显著性差异( χ2 =4 37,v =2 ,P >0 . 0 5) ,在TD组有更高的C/A等位基因频率,与非TD组有显著性差异( χ2 =4 . 36 ,v =1 ,P <0. 0 5)。②不同基因型间的人口学和临床学资料(如:病程、服药总时间、日服抗精神病药物剂量、AIMS和BPRS的评分)间无显著性差异(P >0. 0 5)。结论　5 -HT2A受体基因的A 1 4 38G、T1 0 2C多态性可能与男性精神分裂症患者的TD相关联。     

延边地区朝鲜族、汉族精神分裂症患者5-羟色胺2A受体-1438A/G基因多态性的研究

我们对延边地区朝鲜族、汉族精神分裂症患者进行了5-羟色胺2A受体（5-HT2a）-1438A／G多态性相关性研究。     

精神分裂症与5-羟色胺受体2A多态性相关性研究

目的 探测精神分裂症与5-HT2A受体基因多态性关系。方法用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）技术分析90例精神分裂症患者的5-HT2A受体（T102C）基因多态性，并以90例正常人作为对照。结果 在精神分裂症组和正常对照组中，等住基因A1、A2及基因型A1／A1、A1／A2、A2／A2的差异没有显著性（P〉0．05）。结论 本组样本中5-HT2A受体（T102C）基因多态性与精神分裂症无相关性。提示5-HT2A受体基因（T102C）突变可能不是导致精神分裂症发病的主要因素。     

Serotonin 2A receptor gene polymorphism is not associated with completed suicide.

Several lines of evidence indicate that a serotonergic dysfunction is involved in the biological susceptibility to suicide. Recently, the A-1438G polymorphism of the serotonin 2A (5-HT2A) receptor gene has been suggested to be associated with suicide, but the results are inconsistent. We examined whether the A-1438G polymorphism of the 5-HT2A receptor gene was associated with suicide itself using 151 Japanese completed suicides. No significant difference in genotype distribution or allele frequencies of the polymorphism was found between the completed suicides and the comparison group. We conclude that the A-1438G polymorphism of the 5-HT2A receptor gene is not likely to have a major effect on the biological susceptibility of suicide.     

Association of 5-HT(2A) receptor gene polymorphism with major affective disorders: the case of a subgroup of bipolar disorder with low suicide risk.

BACKGROUND: The implication of serotonin in suicide and affective disease explains why the 5-HT(2A) receptor gene has been proposed as a candidate gene in these disorders, although with conflicting results. METHODS: We analysed the distribution of the 5-HT(2A)-1438A/G genetic polymorphism in 192 patients with major affective disorder (127 bipolar disorders and 65 unipolar disorders) compared to 142 healthy control subjects. RESULTS: We found a higher frequency of the A allele in affected patients than in control subjects (p =.034), this difference being particularly striking for the subgroup of patients with type I bipolar disorder (p =.015). Patients with no personal and/or familial history of suicide attempts mainly accounted for the excess of the A allele in affected patients. CONCLUSIONS: The association detected in this study suggests that the 5-HT(2A) receptor gene may play a role in the genetic susceptibility to bipolar disorder, through a specific subgroup of bipolar type I patients with lower risk of suicidal behavior.     

T102C and -1438 G/A polymorphisms of the 5-HT2A receptor gene in Turkish patients with obsessive-compulsive disorder.

OBJECTIVE: This study aimed to investigate the possible association between T102C and -1438 G/A polymorphism in the 5-HT2A receptor gene and susceptibility to and clinical features of obsessive-compulsive disorder (OCD). METHOD: Fifty-eight patients with OCD and 83 healthy controls were included in the study. All patients were interviewed and rated by Yale-Brown Obsessive-Compulsive Scale. T102C and -1438 G/A polymorphisms of 5-HT2A receptor gene were determined by PCR technique in DNAs of peripheral leucocytes. RESULTS: OCD patients and healthy controls did not show significant differences in genotype distribution for both polymorphisms investigated. We found that frequencies of the TT genotype for T102C polymorphism and the AA genotype for -1438 G/A polymorphism were significantly higher in patients with severe OCD compared to those with moderate or moderate-severe OCD. CONCLUSION: The -1438 G/A and T102C polymorphisms of the 5-HT2A receptor gene are not associated with an increased risk of OCD. Our data suggest that the TT genotype of T102C and the AA genotype of -1438 G/A polymorphism might be a factor in clinical severity of OCD.     

Association between -1438G/A promoter polymorphism in the 5-HT(2A) receptor gene and fluvoxamine response in Japanese patients with major depressive disorder

Genetic polymorphism of the serotonin 5-HT(2A) receptor seems to be associated with therapeutic response to selective serotonin reuptake inhibitors (SSRIs). The present study investigated whether a novel -1438G/A polymorphism in the promoter region of the 5-HT(2A )receptor gene is associated with therapeutic response to fluvoxamine (an SSRI) in 66 Japanese patients with major depressive disorder. Fluvoxamine (50 to 200 mg) was administered twice daily for 6 weeks. Fifty-four patients completed this study. The genotype distribution and the allele frequencies showed no significant difference between responders and non-responders. The time-course of the Montgomery-Asberg Depression Rating Scale scores showed no significant difference among -1438G/G, -1438G/A, and -1438A/A genotype groups. The results demonstrated that the -1438G/A promoter polymorphism in the 5-HT(2A) receptor gene was unlikely to have a major role in therapeutic response to fluvoxamine in Japanese patients with major depressive disorder.     

Polymorphisms in the regulatory region of the human serotonin 5-HT2A receptor gene (HTR2A) influence gene expression.

BACKGROUND: Genomic variation in the regulatory region of the serotonin (5-HT) 2A receptor gene (HTR2A) may contribute to altered levels of 5-HT2A receptor and to psychiatric disease. METHODS: Frequency and linkage disequilibrium (LD) were determined for promoter single nucleotide polymorphisms (SNPs) -1438A/G, -1420C/T, and -783A/G in 156 subjects. Functional relevance of -1438A/G and -783A/G was assayed in vitro using a luciferase reporter assay and ex vivo using quantitative real time polymerase chain reaction in a set of human fibroblast cell lines. RESULTS: Significant LD was observed between SNPs -1438A/G and -783A/G. In vitro assays showed no significant differences in promoter activity between the A- and G-allele of -1438 locus when expressed with the major alleles at -1420C/T and -783A/G; however, when the minor allele G at -783 was expressed with G-allele at -1438, promoter activity was significantly decreased. 5-HT2A receptor mRNA expression in human fibroblast cell lines confirmed that -783A/G polymorphism significantly modified the effects of -1438A/G SNP. CONCLUSIONS: Our results demonstrate that SNP -783A/G modifies the effects of the major SNP -1438A/G. Future studies examining the association of -1438A/G polymorphism with diseases and 5-HT2A receptor expression analyses should account for this epistasis.     

Schizophrenia and the serotonin-2A receptor promoter polymorphism

Serotonin-2A (5-HT2A) receptors have received much investigative attention in schizophrenia because (1) several studies have shown a decrease in the number of 5-HT2A receptors in the prefrontal cortex of postmortem brains of schizophrenic patients; (2) atypical antipsychotic drugs are antagonists for 5-HT2A receptors; and (3) a positive association between a T to C polymorphism at position 102 of the 5-HT2A receptor gene and schizophrenia has been reported. A G to A polymorphism at position -1438 of the 5-HT2A receptor gene was studied in 119 schizophrenic patients and 106 healthy control subjects, all of whom were Japanese. The genotype and allele frequencies did not differ between the patients and control subjects. Furthermore, the genotype frequency did not differ according to diagnostic subtype, family history, age at onset of illness, or daily dosage of antipsychotic medication. Our results suggest that the polymorphism does not contribute to the etiology or clinical characteristics of schizophrenia. However, the gene is greater than 20 kbp in length, and thus it is possible that other areas that affect expression of the gene may vary. We found that the -1438G/A variant was in linkage disequilibrium with the T102C polymorphism.     

Research on serotonin and suicidal behavior: neuroendocrine and molecular approaches

We carried out two studies to test the hypothesis that altered central serotonergic function, as assessed by lower prolactin (PRL) response to fenfluramine (D-FEN), is more closely associated with suicidal behavior than a particular psychiatric diagnosis. A D-FEN test was performed in 85 major depressed inpatients, 33 schizophrenic inpatients, and 18 healthy controls. We showed that PRL response to D-FEN is a marker of suicidality, regardless of psychiatric disorder. We then examined the association en the serotonin (5-hydroxytryptamine) receptor 5-HT(2A) gene polymorphism (T102C) and suicide in a sample of Brazilian psychiatric inpatients (95 with schizophrenia, 78 with major depression) and 52 healthy controls. No differences were found in genotypic frequencies across patients and controls. Overall, no differences were found between patients with (n=66) and without (n=107) a history of suicide attempt. We also compared patients with a history of severe suicide attempts (lethality>3; n=32) and patients without such a history (n=107), but they did not exhibit different genotypic frequencies either. These results show thai the 5-HT(2A) gene polymorphism (T102C) may not be involved in the genetic susceptibility to suicidal behavior.     

Association between seasonal affective disorder and the 5-HT2A promoter polymorphism, -1438G/A

Genes involved in serotonin metabolism are good candidates for the pathogenesis of seasonal affective disorder (SAD). A functional variant in the serotonin transporter promoter, 5-HTTLPR, has recently been shown to be associated with SAD and seasonality. The purpose of this study was to determine whether -1438G/A, a polymorphism in the 5-HT2A promoter, is associated with SAD and seasonality, and whether it has additive effects with 5-HTTLPR on seasonality. Sixty-seven individuals with SAD and 69 normal volunteers, all screened with the SCID and diagnosed according to DSM-III-R criteria, were genotyped for the -1 438G/A 5-HT2A promoter polymorphism. All had been previously genotyped for 5-HTTLPR and had been assessed for seasonality by the Global Seasonality Scale. There was a significant increase in the frequency of the -1438A variant allele of the 5-HT2A promoter polymorphism in SAD patients (0.47) compared to matched controls (0.36) (P < 0.01). The difference in genotype distribution was also significant (P < 0.05). We found no association between the -1438G/A polymorphism and seasonality scores, and there was no additive effect with 5-HTTLPR on seasonality. In conclusion, we have shown that the -1438G/A 5-HT2A promoter variant is associated with SAD but not with seasonality. We suggest that the association may instead be with the depressive symptoms of SAD. However, these results should be treated with caution until replicated because of the possibility of false-positive findings in case-control association studies.     

Genetics of the serotonergic system in suicidal behavior

Genetic factors contribute to the risk of psychopathology in many psychiatric conditions, but the specific genes are yet to be identified. Neurotransmitter alterations are implicated in the etiology of psychopathology based, in part, on studies of neurotransmitter receptors and their biosynthetic or degradative enzymes in postmortem tissue. Identification of the altered receptors and enzymes serves to identify candidate genes of potential etiological significance. Polymorphisms in these genes can contribute to alterations in protein function in vivo that are part of the neurochemical underpinnings of psychopathologies such as major depressive disorder, psychoses, alcoholism, personality disorders, aggressive-impulsive traits, or suicidal behavior. Altered serotonergic function is implicated in the etiology and pathogenesis of several major psychiatric conditions. In particular, there is much evidence for an association of lower serotonergic function and suicidal behavior. Thus genes related to the serotonergic system are candidate genes worthy of study as part of the genetic diathesis for suicidal behavior. This review examines the following polymorphisms in the serotonin biosynthetic enzyme tryptophan hydroxylase (TPH; A779C substitution), the serotonin transporter (5-HTT, 5-HTTLPR allele), the 5-HT(1B) receptor (G861C, C129T substitution) and the 5-HT(2A) receptor (T102C) for their relationship to suicidal behavior. For the TPH gene, we found the less common U or A allele variant of the A779C polymorphism was associated with suicide attempt. Other studies have found the U allele to be associated with aggression and lower serotonergic function in vivo. A 44 base pair insertion/deletion in the 5' flanking promoter region of the 5-HTT gene may result in less 5-HTT expression and 5-HTT binding. We examined 220 cases postmortem and found no association between the promoter genotype and 5-HTT binding. We also found no association with major depressive disorder (MDD), suicide or pathological aggression, despite finding significantly fewer 5-HTT sites in the prefrontal cortex of depressed and/or suicide cases. In genomic DNA samples from 178 unrelated subjects, we detected two polymorphisms for the 5-HT(1B) receptor at nucleotides 861 and 129. However, no association between either polymorphism and depression, suicide, aggression, or alcoholism was observed. There are two common polymorphisms for the 5-HT(2A) receptor gene in humans. The results of studies of 5-HT(2A) receptor gene polymorphisms do not indicate significant major associations with suicidal behavior. In contrast, the 5-HT(2A) receptor itself is reported to be increased in suicide. Functional polymorphisms involving the promoter region that affect gene expression may explain this finding. Studies of candidate genes related to serotonergic function in brain are increasingly used to establish genetic alterations contributing to psychiatric illness. The most meaningful studies combine the study of candidate genes with direct measures of related proteins as well as psychopathology.     

Association of the 5-HT2A receptor gene polymorphism 102 T/C with ischemic stroke

Serotonin (5-HT) has been implicated in a number of cardiovascular disorders due to its ability to induce vascular contraction and platelet aggregation through activation of the 5-HT2 receptor family. In this study, we investigated the association of stroke in a Scandinavian population with two common polymorphisms in the 5-HT2A receptor gene. The two polymorphisms under investigation, namely the 102T/C and the −1438A/G variations of the 5-HT2A receptor gene, were examined in a case control association study involving 99 stroke patients and a comparable number of controls. Among patients, the prevalence of the homozygous 102T/T genotype was significantly higher than in controls (28.3% vs 13.5%; p<0.01). The allelic frequency of 102T carriers was also significantly higher in stroke patients than in controls (p=0.002, OR=1.88, 95%CI, 1.27–2.80). The association between the 102T allele and stroke was significant in both males and females. There was no association between stroke and the −1438A/G polymorphism. Taken together, this study indicates that the 102T/C polymorphism in the 5-HT2A receptor gene could be an independent risk factor for developing stroke.