神经型烟碱乙酰胆碱受体α7亚单位基因多态性与精神分裂症的传递不平衡研究

目的 探讨神经型烟碱乙酰胆碱受体α7亚单位基因(neuronal nicotinic acetyleholine receptor α7 subunit gene,CHRNA7)多态性与精神分裂症的关系.方法 应用聚合酶链反应及聚丙烯酰胺凝胶芯片技术检测129个精神分裂症先证者核心家系CHRNA7基因的rs2337980、rs1909884、rs883473三个单核苷酸多态性,并采用基于单倍型的单倍型相对风险检验(haplotype relative risk,HHRR)、传递不平衡检验(transmission disequilibrium test,TDT)及单倍型分析进行统计.结果 (1)HHRR分析结果显示rs2337980位点精神分裂症患者组与虚拟对照组之间等位基因频率差异有统计学意义(P=0.017);(2)TDT分析发现,rs2337980位点与精神分裂症之间可能存在传递不平衡,杂合子父母过多的传递等位基因C给患病子女(P=0.021).(3)单倍型分析发现,rs2337980、rsl909884及rs2337980、rsl909884、rs883473组成的单倍型与精神分裂症有显著相关(总体P=0.034;glohal P=0.027),其中T-C,T-C-T两个单倍型与精神分裂症可能存在传递不平衡.结论 CHRNA7 基因多态性可能与精神分裂症存在关联,rs2337980的变异等位基因T可能是精神分裂症的保护性因子.     

特应症患者CC16基因多态性分析

研究ＣＣ１６基因多态性与特症遗传易感性之间的关系。方法应用聚合酶链式反应和限制性片段长度多态性方法，观察了４２个特症核心家系中ＣＣ１６基因３８Ａ／Ｇ多态性的遗传分布情况，并用基于单体型的单体型相对风险关联和传递不平衡检验进行关联和连锁分析。     

A meta-analysis of association studies between the 10-repeat allele of a VNTR polymorphism in the 3'-UTR of dopamine transporter gene and attention deficit hyperactivity disorder.

The association between the 10-repeat allele of the dopamine transporter gene (DAT) and attention deficit hyperactivity disorder (ADHD) is uncertain. This study aimed to conduct a meta-analysis of the association between the 10-repeat allele of a variable number tandem repeat (VNTR) polymorphism in the 3'-untranslated region (UTR) of the DAT1 gene and ADHD. We pooled up 18 published transmission disequilibrium test (TDT) studies between the 40-base pair VNTR polymorphism in the3'-UTR of the DAT1 gene and ADHD. It included a total of 1,373 informative meioses, 7 haplotype-based haplotype relative risk (HHRR) studies, and 6 case-control-based association studies. There were statistically significant evidences for heterogeneity of the odds ratio in TDT and HHRR studies (P < 0.10), but not in case-control studies. The results of random effects model showed small but significant association between ADHD and the DAT1 gene in TDT studies (OR = 1.17, 95% CI = 1.05-1.30, chi-square = 8.11, df = 1, P = 0.004), but not in HHRR and case-control studies. The 10-repeat allele of a VNTR polymorphism in the 3'-UTR the DAT1 gene has a small but significant role in the genetic susceptibility of ADHD. These meta-analysis findings support the involvement of the dopamine system genes in ADHD liability variation. However, more work is required to further identify the functional allelic variants/mutations that are responsible for this association.     

FXYD6基因遗传多态性在精神分裂症患者核心家系中的传递不平衡检验

目的 探讨FXYD6基因单核苷酸多态性(single nucleotide polymorphisms,SNP)和精神分裂症(schizophrenia)之间的相关性.方法 采用等位基因特异性PCR的方法对FXYD6基因6个SNPs(rs10790212、rs11544201、rs555577、rs1815774、rs4938446和rs497768)位点的基因型在101个三口之家中进行传递不平衡检验(transmission disequilibrium test,TDT).结果 遗传标记rs10790212和rs11544201显示了显著的传递不平衡(P＜0.05),而单倍型分析的结果表明单倍型rs10790212-rs11544201与精神分裂症显著性关联(P＜0.05).结论 FXYD6基因与中国汉族人群精神分裂症遗传易感性相关,有必要进一步开展对FXYD6基因的功能学研究.     

抑郁症与cAMP反应元件结合蛋白基因的关联研究

目的 探讨cAMP反应元件结合蛋白(cyclic adenosine monophosphate response elementbinding protein,CREB1)基因与抑郁症的关联关系.方法 采用聚合酶链反应-限制性片段长度多态性方法检测105个抑郁症核心家系CREB1基因上单核苷酸多态性(single nucleotide polymorphisms,SNP)rs10932201和rs6740584的等位基因与基因型分布情况.进行单位点及单倍型的传递/不平衡检验(transmission disequilibrium test,TDT).结果 CREB1基因上SNP位点rs10932201和rs6740584与抑郁症均无显著性关联,TDT χ2 值分别为2.700(P=0.1004)和0.458(P=0.4986),差异均无统计学意义.单倍型TDT分析结果显示由rs10932201和rs6740584构成的单倍型与抑郁症存在显著性关联,差异有统计学意义(总χ2=23.458,df=3,P=0.00003241).单个单倍型A-C和A-T与抑郁症也均有显著性关联,差异有统计学意义(χ2 值分别为5.405和13.623,P值分别为0.020和0.00022).结论 CREB1基因上SNP位点rs10932201和rs6740584与抑郁症均无显著性关联,但由这2个SNP位点构成的单倍型与抑郁症存在显著性关联,提示CREB1基因rs10932201-rs6740584单倍型可能在抑郁症的遗传学发病机制中具有重要作用.     

The KPNA3 gene may be a susceptibility candidate for schizophrenia

The present study investigated the possible association of the KPNA3 locus in the 13q14 region with schizophrenia. We detected 7 single nucleotide polymorphisms (SNPs) on 13q14, one (rs6313) present at the HTR2A locus and the other 6 at the KPNA3 locus, among 124 British family trios consisting of mother, father and affected offspring with schizophrenia. The transmission disequilibrium test (TDT) showed allelic association for rs3736830 (chi(2)=8.66, P=0.003), rs2181185 (chi(2)=3.86, P=0.049) and rs626716 (chi(2)=5.82, P=0.016), but not for rs6313 (chi(2)=0.009, P=0.926). The global P-value was 0.029 for 1000 permutations with the TDT. The 2-SNP haplotype analysis showed a disease association for the rs2273816-rs3736830 haplotypes (chi(2)=7.63, d.f.=2, P=0.022), the rs3736830-rs2181185 haplotypes (chi(2)=10.30, d.f.=2, P=0.006) and the rs2181185-rs3782929 haplotypes (chi(2)=9.26, d.f.=2, P=0.01). The global P-value was 0.034 for 1000 permutations with the 2-SNP haplotype analysis. The 6-SNP haplotype system also showed a weak association with the illness (chi(2)=15.62, d.f.=8, P=0.048), although the 1-d.f. test did not show the association for nine individual haplotypes when a P-value was corrected by the Bonferroni corrections. The present study suggests that the KPNA3 may contribute genetically to schizophrenia in a small effect size.     

DAT1 3'-UTR 9R allele: preferential transmission in Indian children with attention deficit hyperactivity disorder.

Genetic alterations in the dopaminergic system are frequently observed in association with attention deficit hyperactivity disorder (ADHD) and a 40 bp variable number of tandem repeats (VNTR) in the 3'-untranslated region (3'-UTR) of the dopamine transporter gene (DAT1) has been investigated in different populations. Both significant association and lack of association with the10 repeat allele (10R) of DAT1 VNTR have been reported. Objective of the present investigation was to examine association of this polymorphism with ADHD in Indian children. Genotypic data obtained from ADHD probands (n = 79), their parents (n = 148) and control individuals (n = 153) were analyzed for haplotype-based haplotype relative risk analysis (HHRR), transmission disequilibrium test (TDT), and family-based association test (FBAT). HHRR analysis revealed significant (P = 0.009) transmission of shorter alleles (< or =9R). TDT analysis of informative ADHD families (n = 32) also exhibited highly significant transmission of the shorter alleles (P = 0.002). Further analysis by FBAT showed preferential transmission (P = 0.019) of the 9R allele from parents to ADHD probands. It can be inferred from the data obtained that the DAT1 3'-UTR 9R allele may confer risk of ADHD in the Indian population.     

Association of the neuropilin-2 (NRP2) gene polymorphisms with autism in Chinese Han population.

Autism is a pervasive neurodevelopmental disorder, with a significant role of genetic factors in its development. The neuropilin-2 (NRP2) gene is localized to 2q34, an autism susceptibility locus. NRP2 has been demonstrated to both guide axons and to control neuronal migration in the central nervous system. It has been reported that NRP2 may be required in vivo for sorting migrating cortical and striatal interneurons to their correct destination. We examine the association between the NRP2 gene and autism using a cohort of 169 Chinese Han family trios. Four single nucleotide polymorphisms (SNPs) were genotyped by the polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analyses. The transmission disequilibrium tests (TDT) of SNPs and haplotype association were carried out using the TDTPHASE program. We found significant genetic association between autism and two of the SNPs of the NRP2 gene (rs849578: P = 0.017, rs849563: P = 0.027), as well as specific haplotypes, especially those formed by rs849563. Furthermore, haplotypes constructed with all markers showed significant excess transmission in both global and individual haplotype analyses (P = 0.004 and 0.017, respectively). The polymorphisms in the NRP2 gene are associated with autism, implying that the NRP2 gene may render individuals to be predisposed to autism.     

A study of the PEMT gene in schizophrenia

The phospholipid hypothesis of schizophrenia is becoming popular because of the findings from the niacin flush test, the treatment with polyunsaturated fatty acids (PUFAs), biochemical studies for the phospholipid metabolism pathway and genetic studies of phospholipase A2. The present study attempted to investigate the gene coding for phosphatidylethanolamine N-methyltransferase (PEMT), which is an important enzyme for the synthesis of membrane phospholipids. We recruited 271 Chinese parent-offspring trios of Han descent and detected 3 single nucleotide polymorphisms (SNPs) at the PEMT locus. The transmission disequilibrium test (TDT) showed allelic association for rs464396 (X2=9.4, P=0.002), but not for the other two. The 2-SNP haplotype analysis showed haplotypic association for both the rs936108-rs464396 haplotypes (X2=25.7, d.f.=3, P=0.00001) and the rs464396-rs4244593 haplotypes (X2=17.3, d.f.=3, P=0.0006). The 3-SNP haplotype analysis also showed a haplotypic association (X2=24.4, d.f.=7, P=0.0006). The present results suggest that the PEMT gene may contribute to the etiology of schizophrenia.     

Family-based association study between autism and glutamate receptor 6 gene in Chinese Han trios.

The glutamate pathways are involved in diverse processes such as learning and memory, epilepsy, and they play important roles in neural plasticity, neural development, and neurodegeneration. It has been proposed that autism could be a hypoglutamatergic disorder. Recently, Jamain et al. reported that the glutamate receptor 6 (GluR6 or GRIK2) is in linkage disequilibrium with autism. In the present study, the transmission disequilibrium test (TDT) and the haplotype transmission were performed to analyze the four SNPs (SNP1: rs995640; SNP2: rs2227281; SNP3: rs2227283; SNP4: rs2235076) of GluR6 in 174 Chinese Han parent-offspring trios. The TDT demonstrated that the two SNPs (SNP2 and SNP3) showed preferential transmission (TDT P = 0.032). The global chi(2) test for haplotype transmission also revealed an association between GluR6 and autism (chi(2) = 10.78, df = 3, P = 0.013). Our results suggested that GluR6 is in linkage disequilibrium with autism.     

Family-based association study between GRIK2 polymorphisms and autism spectrum disorders in the Korean trios

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with strong genetic components. The present study comprises the detection of four single nucleotide polymorphisms (SNPs) in GRIK2 followed by a family-based association analysis of the SNPs in 126 Korean ASD trios by using the transmission disequilibrium test (TDT) and haplotype analysis. We found preferential transmission of the C allele at the rs3213607 (P<0.001) of GRIK2 in ASD and haplotype analysis revealed that one haplotype demonstrated a significant association (P=0.023). These results suggest a potential association between GRIK2 and ASD in the Korean population.     

精神分裂症与KCNN3基因1137～1140缺失移码突变传递不平衡研究

目的 探讨KCNN3基因1137～1140的4个碱基缺失所致移码突变与精神分裂症的关系。方法 95个核心家系共289名家庭成员，包含107例精神分裂症患者纳入本研究。精神分裂症采用CCMD-Ⅱ-R诊断标准。KCNN3基因1137～1140的4个碱基缺失基因型检测使用PCR技术和限制性内切酶DdeI消化方法。精神分裂症与KCNN3基因1137～1140缺失4个碱基的关联分析采用基于单倍型的单倍型相对风险率和传递／不平衡检验。结果 患者组与正常父母组比较，KCNN3基因1137～1140的4个碱基缺失的基因型频数和等位基因频率分布差异无统计学意义（χ^2=0．253，P〉0．05和χ^2＝0．010，P〉0．05）。基于单倍型的单倍型相对风险分析发现父母传递与不传递给患者的KCNN3基因等位基因之间差异无统计学意义（χ^2=0．042，P〉0．05）。传递不平衡检验结果发现KCNN3基因等位基因传递不存在连锁不平衡（χ^2=3．000，P＝0．0833）。结论 本组研究对象中，KCNN3基因第1外显子1137～1140的4个碱基缺失的发生率少；分析结果提示KCNN3基因第1外显子1137～1140的4个碱基缺失的等位基因与精神分裂症无关联。     

A family-based study of Indian subjects from Kolkata reveals allelic association of the serotonin transporter intron-2 (STin2) polymorphism and attention-deficit-hyperactivity disorder (ADHD).

Serotonin transporter (SLC6A4) polymorphisms are variously implicated in mediating susceptibility to attention-deficit-hyperactivity disorder (ADHD), a highly heritable and heterogeneous disorder with onset in childhood. Since there has been no survey in this regard from India, a sample of 56 ADHD cases and 174 healthy individuals from Kolkata were genotyped for the SLC6A4 promoter (5-HTTLPR) and intron-2 (STin2) polymorphisms. We report that the observed distribution of allele frequencies is consonant with that expected as per Hardy-Weinberg equilibrium proportions. Pair-wise combination of alleles comprising the 5-HTTLPR and STin2 polymorphic systems exhibit significant (chi(2) = 14.74, df = 1; P = 0.0001) linkage disequilibrium of low magnitude (D' = 0.269). The estimates of haplotype-based haplotype relative risk (HHRR) (chi(2) = 4.92, P = 0.027; RR = 1.47; 95% CI = 1.01-2.13) and transmission disequilibrium test (TDT) statistics (chi(2) = 7.00, P = 0.008; OR = 3.00; 95% CI = 1.53-5.90) using a family-based study design, indicate significant preferential transmission of the STin2.12 (A12) allele to ADHD cases. Maternal inheritance of the A12 allele is significant in terms of the HHRR (chi(2) = 6.53, P = 0.011; RR = 2.00; 95% CI = 1.08-3.72) and TDT (chi(2) = 8.07, P = 0.005; OR = 6.50; 95% CI = 1.76-23.98) suggesting a novel role for epigenetic mechanisms in the etiology of ADHD. Similar analyses yielded no evidence of association between the 5-HTTLPR polymorphism and ADHD. Studies including additional polymorphic markers, ADHD subjects and other ethnic groups are warranted to further substantiate the present findings.     

Transmission disequilibrium tests confirm the link between DRD4 gene polymorphism and infant attachment.

Following up the results of a previous population association study (Lakatos et al. [2000: Mol Psychiatry 5:633-637; Lakatos et al. [2002: Mol Psychiatry 7:27-31]) by analyses based on parental genetic data confirmed the link between infant attachment and the dopamine D4 receptor (DRD4) gene. Extended transmission disequilibrium tests (ETDT) were performed to determine whether biased transmission of exon III 48 basepair repeat alleles occurred to infants displaying disorganized and secure attachment behavior with their mothers. The overall allele-wise TDTs were significant for both groups (P = 0.038 and 0.020, respectively): a trend for preferential transmission of the seven-repeat allele to disorganized infants was observed (TDT(chi)(2) = 3.27, df = 1, P = 0.071), and there was a significant non-transmission of the same allele to securely attached infants (TDT(chi)(2) = 6.00, df = 1, P = 0.014). Analysis of haplotypes of the exon III repeat and the -521 C/T promoter polymorphisms in family trios showed that the transmission bias in the larger secure group was due to the low-rate transmission of the T.7 haplotype containing both the seven-repeat and the -521 T alleles (TDT(chi)(2) = 4.46, df = 1, P = 0.035). This suggests that not carrying the T.7 haplotype of the DRD4 gene may act as a resilience factor in the optimal development of early attachment.     

Association between polymorphisms in the progesterone receptor gene and endometriosis

The progesterone receptor (PR) is a candidate gene for the development of endometriosis, a complex disease with strong hormonal features, common in women of reproductive age. We typed the 306 base pair Alu insertion (AluIns) polymorphism in intron G of PR in 101 individuals, estimated linkage disequilibrium (LD) between five single-nucleotide polymorphisms (SNPs) across the PR locus in 980 Australian triads (endometriosis case and two parents) and used transmission disequilibrium testing (TDT) for association with endometriosis. The five SNPs showed strong pairwise LD, and the AluIns was highly correlated with proximal SNPs rs1042839 (delta2 = 0.877, D9 = 1.00, P < 0.0001) and rs500760 (delta2 = 0.438, D9 = 0.942, P < 0.0001). TDT showed weak evidence of allelic association between endometriosis and rs500760 (P = 0.027) but not in the expected direction. We identified a common susceptibility haplotype GGGCA across the five SNPs (P = 0.0167) in the whole sample, but likelihood ratio testing of haplotype transmission and non-transmission of the AluIns and flanking SNPs showed no significant pattern. Further, analysis of our results pooled with those from two previous studies suggested that neither the T2 allele of the AluIns nor the T1/T2 genotype was associated with endometriosis.     

支气管哮喘易感区域5q31-33内Tim-3基因单体型分析

目的： 探讨染色体上支气管哮喘易感区域5q31-33内Tim-3基因多态性与支气管哮喘的关系。方法：应用限制性片段长度多态性技术方法,分析了118个儿童变应性哮喘核心家系Tim-3基因4个SNPs(rs10053538、rs10515746、rs13170556和rs9313441)的基因型;采用基于家系传递不平衡检验（TDT）,分析基因分型数据;应用TRANSMIT软件构建单体型并进行单体型关联分析。结果：①基于家系的TDT分析显示,Tim-3基因的4个SNPs由杂合子父母传递给患病子代的等位基因频率不比预期值高,与哮喘无关（P>0.05）。②Transmit多个位点单体型分析结果显示由Tim-3基因rs10053538、 rs13170556、 rs9313441构建的单体型与支气管哮喘有关联（Global 2=10.83,P<0.05）。父母传递给患病子女GGG单体型的观察值小于期望值,差异显著（2=8.24,P<0.01）。结论：中国汉族人群中,位于染色体5q31-33区域的Tim-3基因本身或其附近的基因可能与儿童变应性哮喘的易感性相关。     

Evidence for linkage disequilibrium between the alpha 7-nicotinic receptor gene (CHRNA7) locus and schizophrenia in Azorean families.

Recent studies have suggested that the alpha 7-nicotinic receptor gene (CHRNA7) may play a role in the pathogenesis of schizophrenia. The alpha 7-nicotinic receptor gene (CHRNA7) is involved in P50 auditory sensory gating deficits, and the genomic locus for this gene lies in the chromosome 15q13-14 regions. The human gene is partially duplicated (exons 5-10) with four novel upstream exons. The marker D15S1360 has been shown to be significantly linked with the phenotype of abnormal P50 suppression in schizophrenia families. The marker L76630 is 3 kb in the 3' direction from the last exon of the CHRNA7 gene and is located in the duplicated region. The function of the two L76630 copies is unknown. We genotyped three polymorphic markers D15S1360, D15S165, and L76630 that are localized in a genomic fragment containing the CHRNA7 in 31 Azorean schizophrenia families/trios (including 41 schizophrenia individuals and 97 unaffected families members). An overall analysis utilizing the family-based association test revealed significant linkage disequilibrium between L76630 and schizophrenia (P = 0.0004). Using the extended transmission disequilibrium test and limiting the analysis to one triad per family, transmission disequilibrium of D15S1360 was near significance (P = 0.078). The 15q13 region overlaps with the location of two well-known genomically imprinted disorders: Angelman syndrome and Prader-Willi syndrome. Therefore, we investigated maternal and paternal meioses. We found significant transmission disequilibrium for D15S1360 through paternal transmission (P = 0.0006) in our schizophrenia families. The L76630 marker showed a significant disequilibrium in maternal transmissions (P = 0.028). No parent-of-origin effect was found in D15S165. Overall, our results suggest that the CHRNA7 may play a role in schizophrenia in these families. A parent of origin effect may be present and requires further study.     

Association of IL-1α rs17561 and IL-1 RN rs315952 polymorphisms with Tourette syndrome: a family-based study

Aim: Immune system dysregulation has been implicated to play a key role in pathogenesis of Tourette syndrome (TS). IL-1α and IL-1RN are important inflammatory cytokines that mediate the inflammation. In this study, we investigated the relationship between single-nucleotide polymorphisms (SNPs) of IL-1α and IL-1RN and the susceptibility to TS in Chinese Han population. Methods: A total of 276 children with TS and their parents were recruited in the study. All DNA from our subjects were genotyped for SNPs of IL-1α rs17561 and IL-1RN rs315952 using predesigned TaqMan SNP genotyping assay. The genetic contributions of two polymorphisms were evaluated using transmission disequilibrium test (TDT) and haplotype relative risk (HRR) design. In addition, to increase the efficiency of the test, the haplotype-based HRR (HHRR) was performed. Results: No significant differences were observed in allelic and genotypic frequency of rs17561 in IL-1α and rs315952 in IL-1RN between the transmitted group and non-transmitted group (for IL-1α rs17561: TDT=0.890, df=1, P=0.402; HRR=1.011, X²=3.016, P=0.082, 95% CI=0.999-1.024; for IL-1RN rs315952: TDT=0.095, df=1, P=0.805; HRR=0.984, X²=0.008, P=0.929, 95% CI=0.695-1.394). Similarly, the analysis of HHRR also did not support a significant association (for IL-1α rs17561: HHRR=1.226, X²=0.915, P=0.339, 95% CI=0.807-1.863; for IL-1RN rs315952: HHRR=0.963, X²=0.094, P=0.759, 95% CI=0.758-1.225). Conclusion: Our results suggest that IL-1α rs17561 and IL-1RN rs315952 polymorphisms may not be associated with susceptibility to TS in Chinese Han population. However, the results still need to be replicated in a larger sample size and different populations.     

Human p53 tumor suppressor gene (TP53) and schizophrenia: case-control and family studies

The human p53 tumor suppressor gene (TP53) is considered as a candidate susceptibility gene for schizophrenia because of its functions in neurodevelopment. To test for an association between TP53 and schizophrenia, both the case-control study and the transmission disequilibrium test (TDT) were performed on genotype data from eight polymorphisms in TP53. Our samples included 286 Toronto schizophrenia cases and 264 controls, and 163 Portuguese nuclear families. In the Toronto case-control study significant differences of allele frequencies of the CAA Ins/Del (p=0.027) and the 16bp Ins/Del (p=0.022) were detected. In TDT analysis we found significant differences for transmission of the CAA Ins/Del (p=0.017) in Portuguese schizophrenia families. Haplotype analysis also showed a significant association between TP53 and schizophrenia. These results provide further evidence that TP53 may play a role in the pathogenesis of schizophrenia.