应用复合诱导突变分离PCR法检测mtDNA的单核苷酸多态性

目的应用复合诱导突变分离PCR(multiplexed mutagenically separated PCR,MS-PCR)技术、银染分型,建立线粒体DNA(mitochondrial DNA,mtDNA)编码区单核苷酸多态(single nucleotide polymorphism,SNP)分型系统,探讨其应用价值。并调查了成都汉族群体mtDNA编码区4个SNP基因座等位基因频率和单倍型分布情况。方法根据SNP基因座(C12705T、A8701G、G8584A、C10400T)设计两条片段相差4个碱基的等位基因特异性引物和一条公共引物,4个SNP基因座复合扩增,PCR产物经聚丙烯酰胺凝胶电泳、银染显带后确定样本的基因型。结果不同SNP基因座为长度不同的单一谱带,其分型结果与直接测序一致。在成都汉族160名无关个体中,4个SNP基因座C12705T、A8701G、G8584A、C10400T等位基因频率分别为0.3813/0.6187、0.4813/0·5187、0.8250/0.1750、0.4938/0.5062;共检出6种单倍型,单倍型的基因多样性为0.7137。结论建立的MMS-PCR银染分型系统是一种简单、快速、准确、有效的SNP分型方法,对建立mtDNA编码区SNP数据库,研究群体遗传学、进化学和进行法医学个人识别和亲子鉴定有重要意义。     

云南昆明白族和汉族儿童HLA-DRB1、HLA-DQB1位点基因多态性比较

目的研究昆明白族、汉族人群HLA—DRB1、HLA-DQB1位点的遗传特征。方法采用序列特异性引物（PCR-SSP）方法对昆明70名白族、72名汉族儿童的HLA-DRB1、HLA-DQB1位点等位基因进行分析。结果在HLA-DRB1位点上,昆明白族儿童共检出13个等位基因,汉族检出12个;在HLA-DQB1位点上两组均检出7个等位基因。组间比较HLA—DRB1／DQB1等位基因总体分布及诸多等位基因频率均有显著差异。结论昆明白族和汉族儿童在HLA—DRB1、DQB1等位基因频率分布上既有相似性,又存在差异性。     

Serum lipoprotein(A) profiles in a Singaporean population.

Lipoprotein(a) [Lp(a)] is formed when apolipoprotein(a) is linked to low density lipoprotein (LDL)-cholesterol via a single disulfide bond. It is an independent risk factor for myocardial infarction and raised concentrations are associated with an increased risk of developing coronary artery disease. Singapore has a multi-racial population of 77% Chinese, 14% Malays and 7% Indians. Studies have shown that the Indians have significantly higher standardised mortality ratios (SMR) compared to the Chinese and the Malays. We measured serum Lp(a) concentrations in 803 healthy individuals recruited from the Multiphasic Health Screening Programme, using the Macra Lp(a) sandwich enzyme immunoassay kit (Strategics Diagnostics, Delaware, USA). Lp(a) concentrations were skewed in all three groups. Our population mean was 9.0 mg/dl, with 50th, 75th and 95th percentile values of 10.2, 19.8 and 43.1 mg/dl, respectively, which are lower than values reported from Caucasian populations (15.0, 29.0 and 60.0 mg/dl, respectively). Males had lower Lp(a) concentrations than females (P < 0.05). The Indian group had significantly higher concentrations (median 12.3 mg/dl) compared to their Chinese (median 9.6 mg/dl) and Malay (median 8.4 mg/dl) counterparts (P < 0.05). This could partly account for the higher SMR seen in the Indian population in Singapore. As serum Lp(a) concentrations are method- and population-dependent, we recommend that laboratories determine their own reference ranges by their method to avoid misclassification of the coronary heart disease (CHD) risk of patients.     

我国彝族另一新的DR15(2)等位基因的核苷酸序列分析

目的对在用ＰＣＲ／ＳＳＯ方法作我国彝族群体样本ＨＬＡＤ区寡核苷酸分型中发现的１例ＤＲＢ１的杂合子进行等位基因序列分析。方法用ＤＲＢ基因类引物扩增该特殊的ＤＲＢ１杂合子细胞基因组的ＤＲＢ基因的第二外显子。扩增产物经纯化转染大肠杆菌ＪＭ１０１,克隆后再经酚／氯仿抽提后得到单链Ｍ１３ＤＮＡ。利用ＡＢＩ３７７测序仪自动测序。结果彝族这一特殊的ＤＲＢ１杂合子细胞的ＤＲＢ１基因阳性克隆,经序列分析证实了该ＤＲＢ１杂合子中一个等位基因确为ＤＲＢ１＊１２０２,与ＰＣＲ／ＳＳＯ分型一致;另一个新等位基因ＤＲＢ１＊１５Ｙ２（暂定）等位基因在第二外显子的４７位由编码苯丙氨酸的ＴＴＣ（ＤＲＢ１＊１５０２）变为编码酪氨酸的ＴＡＣ。结论在云南彝族样本中发现的ＤＲＢ１＊１５Ｙ２,其４７位由ＴＡＣ（酪氨酸）置换了相应于ＤＲＢ１＊１５０２的ＴＴＣ（苯丙氨酸）。在我国这样一个多民族国家中,就ＨＬＡ系统而言,可能还有更多新等位基因有待鉴定。这样有助于完善群体遗传资料     

Thymidylate synthase enhancer region: Novel allele in Indians

Background: Thymidylate synthase (TS) is the major target for fluoropyrimidine drugs like 5-Fluorouracil (5-FU). There are polymorphic tandem repeats in the TYMS gene enhancer region (TSER). The number of tandem repeats varies in different populations. The aim of this study was to determine the frequencies of the TSER tandem repeats (rs34743033) and compare the observed frequencies with those of other populations.

Methods: This study genotyped 350 healthy individuals by Polymerase Chain Reaction (PCR).

Results: A novel allele *1 (only a single repeat) was observed in four individuals, the individuals were heterozygous (TSER*1/*2) for TYMS. Another variant rs2853542 affecting the expression of Thymidylate synthase was also analysed. The observed genotype frequencies were compared with frequencies observed in other populations for understanding differences between various population groups. There was a statistically significant difference between Indians and Chinese, Kenyans, Ghanians, African-Americans, Americans of European Ancestry, British, Hungarians, Turkish, Australians and Brazilians.

Conclusion: This study identified a novel single repeat in the TYMS gene which might have an impact on the expression of this gene, which needs to be confirmed by functional studies.     

东亚群体中高血压6WAS阳性9个SNP在中国傣族及蒙古族群体中的验证研究

目的为了验证GwAs研究发现的3个高血压一个基因的相关性。方法本研究选取了3个在东亚群体中被GWAS研究证实了与高血压发生相关的基因（AKAP13,ENPEP和CNNM2）上的9个SNP,在傣族和蒙古族群体中进行验证。对这9个SNPs用SNaPshot的方法在774例傣族群体和409例蒙古族群体中进行了分型,排布单倍型并进行了统计学分析。结果发现统计学上无法证明这9个SNPs与高血压相关。但是在ENPEP基因的一连锁区段中,rs1126483在傣族群体中呈现与收缩压升高弱阳性关联（χ2=4．53,P=0.033）。同时rs3796889在蒙古族群体中也与收缩压的升高呈现弱阳性关联（χ2=4．35,P=0．037）。虽然这一阳性在进行统计学矫正后消失。结论本研究同时在起源不同,生活环境均差异较大的两个群体中均观察到ENPEP基因这一区段与高血压的关联,这也许暗示了此基因确实可能与。高血压发生相关。另一方面本研究的阴性结果,也暗示了中国一些相对封闭的群体可能具有更窄的高血压遗传变异谱。     

A common variant association study reveals novel susceptibility loci for low HDL‐cholesterol levels in ethnic Arabs

The genetic susceptibility to acquiring low high density lipoprotein‐cholesterol (LHDLC) levels is not completely elucidated yet. In this study, we performed a common variant association study for harboring this trait in ethnic Arabs. We employed the Affymetrix high‐density Axiom Genome‐Wide ASI Array (Asian population) providing a coverage of 598,000 single nucleotide variations (SNPs) to genotype 5495 individuals in a two‐phase study involving discovery and validation sets of experiments. The rs1800775 [1.31 (1.22–1.42); p = 3.41E‐12] in the CETP gene and rs359027 [1.26 (1.16–1.36); p = 2.55E‐08] in the LMCD1 gene were significantly associated with LHDLC levels. Furthermore, rs3104435 [1.26 (1.15–1.38); p = 1.19E‐06] at the MATN1 locus, rs9835344 [1.16 (1.08–1.26); p = 8.75E‐06] in the CNTN6 gene, rs1559997 [1.3 (1.14–1.47); p = 9.48E‐06] in the SDS gene and rs1670273 [1.2 (1.1–1.31); p = 4.81E‐06] in the DMN/SYNM gene exhibited suggestive association with the disorder. Seven other variants including rs1147169 in the PLCL1 gene, rs10248618 in the DNAH11, rs476155 in the GLIS3, rs7024300 in the ABCA1, intergenic rs10836699, rs11603691 in P2RX3 and rs750134 in CORO1C gene exhibited borderline protective properties. Validation and joint meta‐analysis resulted in rs1800775, rs3104435 and rs359027 retaining their predisposing properties, while rs10836699 and rs11603691 showed protective properties. Our data show several predisposing variants across the genome for LHDLC levels in ethnic Arabs.     

Clinical and molecular insights into Glanzmann's thrombasthenia in China

Glanzmann's thrombasthenia (GT) is a rare bleeding disorder characterized by spontaneous mucocutaneous bleeding. The disorder is caused by quantitative or qualitative defects in integrin αIIbβ3 (encoded by ITGA2B and ITGB3) on the platelet and is more common in consanguineous populations. However, the prevalence rate and clinical characteristics of GT in non‐consanguineous populations have been unclear. We analyzed 97 patients from 93 families with GT in the Han population in China. This analysis showed lower consanguinity (18.3%) in Han patients than other ethnic populations in GT‐prone countries. Compared with other ethnic populations, there was no significant difference in the distribution of GT types. Han females suffered more severe bleeding and had a poorer prognosis. We identified a total of 43 different ITGA2B and ITGB3 variants, including 25 previously unidentified, in 45 patients. These variants included 14 missense, 4 nonsense, 4 frameshift, and 3 splicing site variants. Patients with the same genotype generally manifested the same GT type but presented with different bleeding severities. This suggests that GT clinical phenotype does not solely depend on genotype. Our study provides an initial, yet important, clinical and molecular characterization of GT heterogeneity in China.     

Internet-Based,Culturally Sensitive,Problem-Solving Therapy for Turkish Migrants With Depression: Randomized Controlled Trial

Background

Turkish migrants living in the Netherlands have a high prevalence of depressive disorders, but experience considerable obstacles to accessing professional help. Providing easily accessible Internet treatments may help to overcome these barriers.

Objective

The aim of this study was to evaluate the effectiveness of a culturally sensitive, guided, self-help, problem-solving intervention through the Internet for reducing depressive symptoms in Turkish migrants.

Methods

A two-armed randomized controlled trial was conducted. The primary outcome measure was the severity of depressive symptoms; secondary outcome measures were somatic symptoms, anxiety, quality of life, and satisfaction with the treatment. Participants were assessed online at baseline, posttest (6 weeks after baseline), and 4 months after baseline. Posttest results were analyzed on the intention-to-treat sample. Missing values were estimated by means of multiple imputation. Differences in clinical outcome between groups were analyzed with a t test. Cohen’s d was used to determine the between-groups effect size at posttreatment and follow-up.

Results

Turkish adults (N=96) with depressive symptoms were randomized to the experimental group (n=49) or to a waitlist control group (n=47). High attrition rates were found among the 96 participants of which 42% (40/96) did not complete the posttest (6 weeks) and 62% (59/96) participants did not complete the follow-up assessment at 4 months. No significant difference between the experimental group and the control group was found for depression at posttest. Recovery occurred significantly more often in the experimental group (33%, 16/49) than in the control group (9%, 4/47) at posttest (P=.02). Because of the high attrition rate, a completers-only analysis was conducted at follow-up. The experimental group showed significant improvement in depression compared to the control group both at posttest (P=.01) and follow-up (P=.01).

Conclusions

The results of this study did not show a significant effect on the reduction of depressive symptoms. However, the effect size at posttest was high, which might be an indicator of the possible effectiveness of the intervention when assessed in a larger sample and robust trial. Future research should replicate our study with adequately powered samples.

Trial Registration

Dutch Trial Register: NTR2303. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2303 (Archived by WebCite at http://www.webcitation.org/6IOxNgoDu).