原发性失眠的5-羟色胺转运体基因遗传多态性研究

目的　探讨原发性失眠与羟色胺转运体( 5 -HTT)基因遗传多态性的关系。方法　对85例病例组和54名对照组提取外周血基因组DNA ,进行PCR扩增,分析相应的基因型,并比较两组不同基因型患者的焦虑和抑郁评分有无差异。结果　两组的5 -HTTLPR和5 -HTTVNTR的基因型、等位基因频率及不同基因型频率的两两比较均无显著性差异(P >0 .0 5) ;病例组5- HTTLPR的S/S(S组)和S/L +L/L(L组)两组之间及5- HTTVNTR的1 0 / 1 0 + 1 0 / 1 2 ( 1 0组)和1 2 / 1 2 ( 1 2组)两组之间的焦虑、抑郁量表评分比较均无显著性差异(P >0 . 0 5)。结论　5- HTTLPR和5 -HTTVNTR两种基因遗传多态性与原发性失眠的关系尚需进一步探讨。     

中国汉族人群5-羟色胺转运体基因多态性与非病灶性颞叶癫痫的关联性

目的　初步探讨颞叶癫痫(temporal lobe epilepsy,TLE)的遗传易感因素。方法　采用聚合酶链反应技术,检测263例TLE患者和296名健康对照者的5-羟色胺转运体(5-hydroxytryptamine transporter,5-HTT) 基因启动子的基因连锁多态区(gene-linked polymorphic region,LPR) 和第2内含子的可变数目串联重复区(variable number tandem repeat,VNTR) 多态性,分别对所得基因型和等位基因的频率进行相关统计学分析。结果　TLE患者5-HTTLPR多态性的基因型和等位基因频率与正常对照组之间的差异无统计学意义(P>0.05)。TLE患者的5-HTTVNTR的基因型12/12频率高于正常对照组(P<0.01),其等位基因12的频率高于正常对照组(P< 0.01)。携12等位基因者患TLE的相对危险度(OR)是1.435,95%可信区间(CI)为1.096～1.880(P<0.05)。 结论　5-HTTLPR可能不是TLE患者的遗传位点,第2内含子VNTR的等位基因12可能与TLE有一定的关联。     

Possible Association between Serotonin Transporter Gene Polymorphism and Suicide Behavior in Major Depressive Disorder

Objective

The serotonin transporter (5-HTT) genes are major candidate genes for modulating the suicidal behavior. We investigated the association between serotonin transporter polymorphisms and suicidal behavior in patients with major depressive disorder (MDD).

Methods

Serotonin transporter intron 2 VNTR polymorphism (5-HTTVNTR) and serotonin transporter linked polymorphic region polymorphism (5-HTTLPR) were analyzed in 132 depressed patients with suicidal attempt as well as in 122 normal controls. Hamilton''s 17-item Depression Rating Scale (HDRS), the Risk-Rescue rating system (RRR) and the Lethality Suicide Attempt Rating Scale updated (LSARS-II) were assessed for the depressed patients.

Results

Although not statistically significant, a trend was found such that the 10/10 and 10/12 alleles of 5-HTTVNTR were more common in suicidal subjects than in control subjects. Comparing allele frequency, those with a 10 allele or 10 allele carriers were higher in suicidal subjects than in control subjects. No difference was noted in 5-HTTLPR genotypes and haplotype distribution between the suicidal subjects and control subjects. The RRR scores in subjects with the 10/10 5-HTTVNTR genotype or 10 5-HTTVNTR allele were significantly lower than those in subjects with other genotypes.

Conclusion

These results show the possibility that 10 allele of 5-HTTVNTR is related to suicidal behavior in the suicidal subjects with MDD and suggest that 12 allele of 5-HTTVNTR might be related to more lethality in the suicidal subjects with MDD.     

Association study for a functional serotonin transporter gene polymorphism and late-onset Alzheimer's disease for Chinese patients.

Two recent studies have demonstrated an association for a deletion/insertion polymorphism within the promoter region of the serotonin transporter gene (5-HTTLPR), and Alzheimer's disease (AD). According to these studies, subjects with the short variant of the 5-HTTLPR gene are at increased risk for AD; however, this finding has not been confirmed by other workers. To evaluate the role of the 5-HTTLPR gene in susceptibility for AD, we conducted an association study for this polymorphism in a Chinese population. No significant differences were determined for genotype distribution or allele frequencies, comparing AD patients and normal controls. Even dividing the population into subgroups according to the presence of the APOE epsilon4 allele, no differences for genotype or allele frequencies were determined, comparing patients and controls. These results suggest that it is unlikely that the 5-HTTLPR polymorphism plays a substantial role in conferring susceptibility to AD.     

Serotonin transporter gene polymorphisms and hyperserotonemia in autistic disorder.

Previous studies have provided conflicting evidence regarding the association of the serotonin transporter (5-HTT) gene with autism. Two polymorphisms have been identified in the human 5-HTT gene, a VNTR in intron 2 and a functional deletion/insertion in the promoter region (5-HTTLPR) with short and long variants. Positive associations of the 5-HTTLPR polymorphism with autism have been reported by two family-based studies, but one found preferential transmission of the short allele and the other of the long allele. Two subsequent studies failed to find evidence of transmission disequilibrium at the 5-HTTLPR locus. These conflicting results could be due to heterogeneity of clinical samples with regard to serotonin (5-HT) blood levels, which have been found to be elevated in some autistic subjects. Thus, we examined the association of the 5-HTTLPR and VNTR polymorphisms of the 5-HTT gene with autism, and we investigated the relationship between 5-HTT variants and whole-blood 5-HT. The transmission/disequilibrium test (TDT) revealed no linkage disequilibrium at either loci in a sample of 96 families comprising 43 trios and 53 sib pairs. Furthermore, no significant relationship between 5-HT blood levels and 5-HTT gene polymorphisms was found. Our results suggest that the 5-HTT gene is unlikely to play a major role as a susceptibility factor in autism.     

Association between apolipoprotein CI HpaI polymorphism and sporadic Alzheimer's disease in Chinese

OBJECTIVE: To investigate into the relationship of apolipoprotein CI (ApoCI) polymorphism with sporadic Alzheimer's disease (AD) in Chinese. SUBJECTS AND METHODS: A total of 257 AD patients and 242 age-matched elderly individuals were genotyped for the ApoCI HpaI and apolipoprotein E (ApoE) HhaI polymorphisms. RESULTS: The ApoCI A allele was associated with AD of moderate to severe dementia when patients were divided into two subgroups according to Clinical Dementia Rating scale, and the AA genotype was strongly associated with moderate to severe AD in ApoE epsilon4 allele carriers [odds ratio (OR) = 8.19, 95% confidential interval: 1.28-52.30, after adjusting for age and gender by logistic regression analysis], although in total no significant differences of allele or genotype frequency between patients and controls were found. CONCLUSION: The present study partially confirmed the previous findings, suggesting that the ApoCI A allele might contribute to the susceptibility to moderate to severe sporadic AD in Chinese.     

偏头痛与5-羟色胺转运体基因多态性的相关性研究

目的研究5-羟色胺转运体(5-hydroxytryptamine transporter,5-HTT)基因多态性频率在汉族偏头痛人群的分布,探讨该基因多态性与偏头痛的相关性。方法采集40例偏头痛患者(实验组)和40例健康成人(对照组)的肘静脉血,通过DNA-PCR扩增等分子生物学技术,观察5-HTT基因多态性的基因型和等位基因频率在两组中的分布特点。结果5-HTT基因多态性的基因型和等位基因频率在实验组和对照组中的分布无统计学差异(P>0.05),在偏头痛各临床特征中的分布也无统计学差异(P>0.05)。结论5-HTT基因是否在汉族人群偏头痛发病中起作用,有待进一步研究。     

Apolipoprotein E and intronic polymorphism of presenilin 1 and alpha-1-antichymotrypsin in Alzheimer's disease and vascular dementia

Apolipoprotein E (ApoE) genotypes, presenilin 1 (PS-1) and alpha(1)-antichymotrypsin (ACT) polymorphism and the association of the genotypes were examined in patients with Alzheimer's disease (AD, n = 121) or vascular dementia (VD, n = 68) in comparison with elderly controls (n = 125). The frequency of the ApoE epsilon 4 allele was significantly increased both in late-onset AD (0.35) and in VD (0.17); the frequency of ApoE epsilon 2 was significantly reduced in AD, but it was similar in VD and controls. The presence of the allele 1 of PS-1 intronic polymorphism was not associated with AD or VD and was not influenced by the ApoE genotypes. Also, the frequency of allele A of the intronic polymorphism of ACT was similar in AD, VD and controls and it was not altered by ApoE or PS-1 genotypes. The results confirm the association between ApoE epsilon 4 and AD and indicate an increase in ApoE epsilon 4 in Vd, too. A potential protective role of ApoE epsilon 2 is also suggested for late-onset AD but not for VD. No association was shown between ACT allele A and PS-1 allele 1 in AD or VD.     

Serotonin transporter gene polymorphism and schizoid personality traits in the patients with psychosis and psychiatrically well subjects.

BACKGROUND AND OBJECTIVES: serotonin transporter (5-HTT) gene allelic variants were shown to be associated with Neuroticism and Harm Avoidance but the results were not replicated in other studies. The current investigation was undertaken in a further attempt to study the relationship between 5-HTT polymorphism and personality traits. SUBJECTS AND METHODS: to evaluate a spectrum of personality traits, MMPI was administered to a sample including patients with affective disorders (n=114), patients with schizophrenia spectrum illnesses (n=110) and psychiatrically well controls (n=124). All groups were genotyped for VNTR-17 and functional insertion-deletion (5-HTTLPR) polymorphisms. RESULTS: an association was found between 5-HTTLPR polymorphism and scores on three MMPI scales: Psychopathic deviance, Paranoia and Schizophrenia in patients with affective disorders and S chizophrenia in normal subjects. Both affected and control individuals with 'ss' genotype exhibited lower scores on these scales. CONCLUSION: we demonstrated that functional deletion/insertion allelic variation associated with decreased expression of serotonin transporter ('s' allele or 'ss' genotype) may restrict expression of schizoid traits in normal subjects and patients with affective disorders.     

Effect of APOE genotype and promoter polymorphism on risk of Alzheimer's disease

OBJECTIVE: To verify the association between APOE gene promoter polymorphisms and the development of AD and to determine whether the effect of promoter polymorphisms on AD is independent of the APOE epsilon4 allele. BACKGROUND: Three polymorphisms in the APOE promoter have been shown to modify APOE expression in vitro. Several studies have suggested that these polymorphisms may also modulate risk for AD, either independently or by modifying the effect of the APOE coding polymorphism. METHODS: The authors analyzed allele and genotype distributions for APOE and all three known APOE promoter polymorphisms (-491 A/T, -427 T/C, and -219 G/T) in a study group consisting of 237 subjects with AD and 274 age-matched controls. They then used log-linear and logistic regression analyses to test for possible interactions between APOE genotype and the promoter polymorphisms on risk of AD. CONCLUSION: A strong association between the APOE epsilon 4 allele and AD was detected regardless of promoter polymorphism status. In addition, the -491 AA genotype appears to be an independent genetic risk factor for AD. The -427 T/C polymorphism and the -219 T/G polymorphism were not directly associated with AD.     

5-羟色胺转运体基因多态与共患学习困难的儿童注意缺陷多动障碍的相关性

目的探讨共患学习困难(LD)的注意缺陷多动障碍(ADHD)患儿与5-羟色胺转运体(5-HTT)基因连锁多态区(5-HTTLPR)和第2内含子17 bp数目可变的顺向重复(stin2.VNTR)的关联关系。方法对126例共患LD的ADHD患儿和198例不共患LD的ADHD患儿的5-HTTLPR和stin2.VNTR两种多态进行检测,并采用传递不平衡检测(TDT)和单体型分析方法进行关联分析。结果(1)TDT检测:5-HTTLPR多态的S等位基因在共患LD的ADHD和ADHD混合型(ADHD-C)核心家系中优先传递(X2=5.831和5.281,P=0.015和0.020);所有家系均未观察到stin2.VNTR多态中的任何等位基因有传递不平衡现象(均P>0.05);(2)单体型分析:5-HTT基因与共患LD的ADHD和ADHD-C相关联(X2=11.391和13.343,v=3,P=0.010和P=0.004);单体型L／12在共患LD的ADHD和ADHD-C核心家系中传递较少(X2=10.317和8.948,v=1,P=0.001和0.003),而单体型L／10在共患LD的ADHD核心家系中传递较多(X2=4.065,v=1,P=0.044)。结论5-HTT基因可能与共患LD的ADHD相关联,其中主要为共患LD的ADHD-C亚型。     

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5- 羟色胺转运体( 5 -HTT)基因启动子区多态性与注意缺陷多动障碍(ADHD)及其相关症状的关系。方法　抽取1 39例ADHD患儿及1 1 5名正常对照,用Achenbach儿童行为调查表(CBCL)来评定患者的临床症状;采用聚合酶链式反应(PCR)、聚丙烯酰胺凝胶电泳结合银染技术,检测ADHD患者和对照组基因型和等位基因的频率。结果　患者组5- HTT启动子区多态性( 5- HTTLPR)的基因型和等位基因的频率与对照组相比无显著性差异(P >0. 0 5) ;但发现S/S基因型个体社会退缩、躯体主诉两行为分量表评分高,S/S基因型个体与S/L +L/L基因型个体间社会退缩、躯体主诉两分量表分有显著性差异(P <0 . 0 5)。结论　本研究结果不支持5- HTTL- PR与ADHD存在关联,但ADHD的某些内化性症状与5 -HTTLPR可能存在关联。     

Apolipoprotein E phenotypes in demented and cognitively impaired patients with and without cerebrovascular disease

Controversy exists regarding the apolipoprotein E (ApoE) epsilon4 allele association with vascular dementia (VaD), ranging from increased epsilon4 frequency, similar to that found for Alzheimer's disease (AD), to no association between the epsilon4 allele and VaD. To clarify further the relationship between ApoE alleles polymorphism and cerebrovascular disease (CVD) in demented and cognitively impaired patients, we examined the ApoE phenotypes in a sample of 280 patients: 155 with AD, 21 with VaD, 32 with mixed dementia (MD), 45 with mild cognitive impairment (MCI) but without CVD, and 27 in which vascular disease was the most probable cause of cognitive decline [vascular mild cognitive impairment (VMCI)]. Our results show that the frequency of the ApoE epsilon4 allele in patients over 70 years old with clinically diagnosed VaD and VMCI does not differ significantly from that of controls. In contrast, ApoE epsilon4 allele-bearing individuals had greater risk of having late-onset AD (OR = 8.8; 95% CI 3.7-21.0), or non-vascular cognitive impairment (OR = 7.0; 95% CI 2.5-19.0).     

Polymorphisms of APOE and LRP genes in Brazilian individuals with Alzheimer disease

Alzheimer disease (AD) is the most frequent cause of dementia in Western countries. Putative genetic risk factors for AD are polymorphisms in the apolipoprotein E (APOE) gene and in the low-density lipoprotein receptor-related protein (LRP) gene. Our objective was to investigate the role of the APOE coding region polymorphisms epsilon 2, epsilon 3, and epsilon 4 and APOE promoter variants A/T at position -491 and G/T at -219, as well as LRP polymorphism C/T, as risk factors for AD in Brazilian individuals. One hundred and twenty patients with probable AD, along with 120 controls were analyzed. A significant difference between patients and controls for epsilon 4 alleles was observed: frequency of this allele in AD was 0.31, and 0.10 in controls. Individuals with 2 epsilon 4 alleles had a higher risk for AD than subjects with only 1 such allele; presence of 1 epsilon 2 allele proved protective. The presence of the T allele of the -219 polymorphism was also associated with an increased risk of AD, but this polymorphism is in linkage disequilibrium with APOE epsilon polymorphisms. No significant differences between patients and controls were observed for -491 APOE or LRP polymorphisms. In this Brazilian population, both the epsilon 4 allele and T -219 polymorphism were associated with an increased risk for AD.     

Association between apolipoprotein E epsilon4 allele and apathy in probable Alzheimer's disease

OBJECTIVE: There have been inconclusive results to date on the association between the Apolipoprotein E (ApoE) genotype and neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD). We investigated whether ApoE epsilon4 allele is associated with NPS in probable AD. METHOD: Data for 197 subjects with probable AD were analysed. The Neuropsychiatric Inventory was used to evaluate the frequency and severity of NPS. Multiple logistic regression models were used to test the association between ApoE genotype and NPS in AD. RESULTS: The ApoE epsilon3/3 genotype was present in 52.3%, epsilon3/4 in 44.1%, and epsilon4/4 in 3.6% of patients. ApoE epsilon4 carriers showed a higher frequency of apathy than non-carriers. After multiple adjustments, the ApoE epsilon4 allele was significantly associated with apathy. CONCLUSION: Our results suggest a relationship between the ApoE epsilon4 allele and apathy in patients with AD.     

How the serotonin transporter 5-HTTLPR polymorphism influences amygdala function: the roles of in vivo serotonin transporter expression and amygdala structure

The serotonin transporter-linked promoter region (5-HTTLPR) polymorphism of the serotonin transporter gene is associated with amygdala response during negative emotion. The aim of this study was to investigate whether this genotype effect on amygdala function is mediated by current serotonin transporter (5-HTT) levels or rather by genetically induced influences during neurodevelopment, shaping brain structure. A total of 54 healthy subjects underwent functional and structural magnetic resonance imaging, [¹¹C]DASB positron emission tomography and 5-HTTLPR genotyping to analyze the interrelationships between amygdala activation during processing of unpleasant stimuli, 5-HTTLPR genotype, amygdala volumes and 5-HTT levels in the midbrain and in other brain regions. In line with previous research, carriers of the short allele (S) showed increased amygdala activation. Path analysis demonstrated that this genotype effect was not procured by current 5-HTT availability but by amygdala structure, with smaller amygdala volumes in the S than in the LL genotype, as well as smaller volumes being associated with increased amygdala activation. Our findings stress the role of genetic effects during neurodevelopment.     

A polymorphism (5-HTTLPR) in the serotonin transporter promoter gene is associated with DSM-IV depression subtypes in seasonal affective disorder

Serotonergic mechanisms are thought to play an important role in the pathogenesis of seasonal affective disorder (SAD). The expression of the serotonin transporter (5-HTT) is regulated in part by an insertion/deletion polymorphism in the serotonin transporter gene promoter region (5-HTTLPR). The 5-HTTLPR short allele (s) has been associated with anxiety-related personality traits and depression, and one study observed an association between the 5-HTTLPR s-allele and SAD and the trait of seasonality. We genotyped 138 SAD patients and 146 healthy volunteers with low seasonality for 5-HTTLPR. No difference between patients and controls was found for genotype distribution and s-allele frequency. However, genotype distribution and allele frequencies were strongly associated with DSM-IV depression subtypes. Melancholic depression was associated with the 5-HTTLPR long (l) allele and atypical depression with the 5-HTTLPR s-allele (two-sided Fisher's exact test: genotype distribution: P=0.0038; allele frequencies: P=0.007). Our data are compatible with the hypothesis of a disease process that is not causally related to 5-HTTLPR, but involves 5-HT neurotransmission and 5-HTTLPR somewhere on its way to phenotypic disease expression.     

Serotonin transporter polymorphisms and persistent, pervasive childhood aggression

OBJECTIVE: The purpose of this study was to examine the potential association of the serotonin transporter (5-HTT) gene and childhood aggression by testing the 5-HTT variable-number-tandem-repeat and serotonin transporter promoter polymorphism (5-HTTLPR), including the recently discovered Lg allelic variant of 5-HTTLPR. METHOD: Clinically referred children displaying extreme aggression, with a minimum 2-year history, were genotyped for 5-HTTLPR (N=77) and 5-HTT variable-number-tandem-repeat (N=78). Analyses compared genotype frequencies of the aggressive children with healthy comparison subjects. RESULTS: The "low expressing" genotypic variants of the 5-HTTLPR polymorphism (S/S, Lg/S, Lg/Lg) were significantly associated with childhood aggression. CONCLUSIONS: This is the first study to report a significant association between the 5-HTTLPR gene and childhood aggression.