中国人群脂蛋白脂肪酶基因突变与高脂血症的相关性研究

为进行脂蛋白脂肪酶基因突变与中国人群高脂血症的相关性研究,采用单链构象多态性分析结合DNA序列测定的方法,对386例(其中108例高脂血症患者,278例正常对照)中国人群进行突变筛查。结果发现1个新的沉默突变L103L,1个错义突变P207L,3个剪接突变Int3/3′-ass/C(-6)→T和普遍存在的S447X多态性,其中发生在高脂血症组的P207L杂合子为亚洲首报,并对先证者的家系进行了研究,认为P207L是家族性高脂血症的病因之一,而在正常对照组中也有发现的Int3/3′-ass/C(-6)→T,对以往研究认为其是高脂血症易患因素的观点提出了相反的报告,对于普遍认为有益的多态性位点S447X,进一步研究认为其对于正常人群,特别是健康男性的保护作用更强。结论:脂蛋白脂肪酶基因变异与高脂血症的相关性十分复杂多样,大规模的人群筛查具有重要意义。     

α2-HS 糖蛋白基因与中国人群的髋部骨大小的相关性研究

骨大小是一种独立于骨密度（BMD）的骨质疏松性骨折的重要风险因子。由于其高遗传率,充分了解控制骨大小的遗传因素有很重要的临床意义。文章研究目的为检测中国人群中α2-HS糖蛋白基因（AHSG）多态性和腰椎及髋部骨大小变异之间的关联。我们总共征集了来自中国401个核心家庭（包括父母亲及至少一个女儿）的1260个研究样本,并且分型了AHSG基因第7个外显子的Sac Ⅰ位点多态性。该位点核苷酸的替换（C→G）引起第238号丝氨酸被苏氨酸取代,因此可能对基因功能有影响。在任何骨骼位点,没有发现显著的群体分层。发现-HSG基因SacⅠ位点多态性和转子间（P=0．019）以及全髋的（P=0．035）骨大小呈显著性相关。该多态性位点能分别解释转子间和全髋3．74％和3．16％的骨大小变异。连锁分析没有检测到显著性结果,可能的主要原因是样本中同胞对的数目较少,统计效力较低,以及SacⅠ位点多态相对于微卫星标记对连锁分析提供的信息量少。结果表明,月HSG基因多态性可能和中国人群中髋部骨大小变异有关。     

一组中国河南汉族群体血管紧张素转换酶基因多态性与血清酶活性研究

为研究中国汉族群体血管紧张素转换酶(angiotensin-1 converting enzyme,ACE)活性、基因多态性分布及相互关系,用分光光度法检测496例汉族个体血清酶活性,PCR后的限制性酶切片段长度多态性(PCR-RFLP)法检测血管紧张素转换酶基因启动子区A-5466C、T-3892C、A-240T及编码区T1237C、G2215A、G2350A共6个SNP位点,以及第16内含子的A／u片段插入／缺失(I／D)和3’端4656(CT)。共8个多态位点的分布,同时用最大期望值(expectationmaximization,EM)算法估计基因连锁不平衡状态和单倍型结构。结果发现,上述8个多态存在于常见的9个单倍型中,其中两种最常见的单倍型为A(A-T-A-T-G-I-A-3)和B(C-C-T-C-A-D-G-2),A和B在每个位点都不相同。最大简约法分析提示本群体可被分为3个进化簇,Ⅲ簇最有可能由Ⅰ簇和Ⅱ簇产生。ACE基因各位点多态性在个体中的分布与血清中ACE活性有关,组成单倍型A的各等位位点与血清中ACE低活性有关,单倍型B的各等位位点与血清中ACE高活性有关。研究结果提示,本群体中ACE基因存在连锁不平衡,有两种主要的单倍型,单倍型B可能与导致ACE升高的数量性状(QTL)关联,但确定具体的数量性状位点还需绘制精细物理图谱。     

Association of the HindIII Polymorphism of the Lipoprotein Lipase Gene with Myocardial Infarction and the Life Span in Elderly Patients with Coronary Heart Disease

Allele and genotype frequencies of the HindIII polymorphism of the lipoprotein lipase (LPL) gene were studied in patients with myocardial infarction (MI) and stable angina of effort (SAE), including long-lived people (over 90). The polymorphism proved to be associated with MI and with the life span, genotype H+/H+ being predisposing to MI and allele H– being protective. The allele and genotype frequencies of long-lived people differed significantly from the Hardy–Weinberg proportions and from those of SAE patients aged up to 90. An excess of heterozygotes in this group suggests a selective pressure which eliminates homozygotes. Possibly, heterozygotes H+/H– have an adaptive advantage, which provides for their longevity.     

TNFR2基因的CA重复多态性在两个独立的白人群体中与肥胖表型的连锁和关联

我们先前通过全基因组扫描发现lp36与体重指数显提示性连锁（LOD=2．09）。肿瘤坏死因子受体2（1NFR2）定位于lp36,是肥胖的一个极好的图位和功能侯选基因。本研究采用数量传递连锁不平衡检验在两个大的独立的白人样本中进行了TNFR2基因与肥胖表型的连锁与关联检验。第一组受试者由来自79个多代家系的1836个个体组成;第二组受试者由来自157个核心家庭的636个个体组成。所检测的肥胖表型包括体重指数、脂肪量和脂肪量百分数。在多代家系中我们发现TNFR2基因变异与BMI显著连锁（P=0．0056）。结果表明,TNFR2基因是影响白人BMI变异的一个数量性状位点。     

Commentary on "Genetic linkage and transmission disequilibrium of marker haplotypes at chromosome 1q41 in human systemic lupus erythematosus", by RR Graham et al.

Genome-wide linkage analysis studies in families with systemic lupus erythematosus (SLE) have revealed consistent evidence of linkage to several regions of the genome. In a previous issue of this journal, Graham and colleagues described their approach to following up the linkage data for one of these regions, 1q41–42. Using methods based on the transmission disequilibrium test, the region likely to harbour a SLE disease gene was refined to 2.3 Mb. This commentary discusses their approach and identifies lessons that may be applicable to the investigation of other complex diseases.     

黔北人群TGFα基因多态性与非综合征性唇腭裂的相关性研究

本研究旨在探讨黔北地区人群TGFα基因3个SNP位点的多态性及其与非综合征性唇腭裂的相关性。采用PCR和测序方法对86个对照儿童(其中核心家系41例)和116个NSCL/P儿童(其中核心家系52例)的TGFα基因rs11466297、rs473698和rs115055578 3个SNP位点进行扩增和测序;对样本群体进行Hardy-weinberg平衡检测,对2组人群进行基因型频率、等位基因频率比较及OR分析;对病例组核心家系进行HHRR和TDT检验。对照组与病例组人群rs11466297基因型均为AA野生型,rs473698位点包含GG型、GC型和CC型,rs115055578位点基因型均为GG野生型。对于rs473698位点,对照组和病例组均符合Hardy-Weinberg平衡法则(p>0.05),2组人群的基因型和等位基因频率分布差异均无统计学意义(p<0.05);rs473698位点未发现传递不平衡现象(p>0.05)。黔北地区人群TGFα基因rs11466297和rs115055578位点以野生纯合型为主,rs473698位点具有多态性,但其多态性与黔北地区人群区非综合征性唇腭裂的发生可能没有相关性。     

Multi-allelic haplotype association identifies novel information different from single-SNP analysis: A new protective haplotype in the LRP8 gene is against familial and early-onset CAD and MI

Our previous studies identified a functional SNP, R952Q in the LRP8 gene, that was associated with increased platelet activation and familial and early-onset coronary artery disease (CAD) and myocardial infarction (MI) in American and Italian Caucasian populations. In this study, we analyzed four additional SNPs near R952Q (rs7546246, rs2297660, rs3737983, rs5177) to identify a specific LRP8 SNP haplotype that is associated with familial and early-onset CAD and MI. We employed a case–control association design involving 381 premature CAD and MI probands and 560 controls in GeneQuest, 441 individuals from 22 large pedigrees in GeneQuest II, and 248 MI patients with family history and 308 controls in an Italian cohort. Like R952Q, LRP8 SNPs rs7546246, rs2297660, rs3737983, and rs5177 were significantly associated with early-onset CAD/MI in both population-based and family-based association studies in GeneQuest. The results were replicated in the GeneQuest II family-based population and the Italian population. We then carried out a haplotype analysis for all five SNPs including R952Q. One common haplotype (TCCGC) was significantly associated with CAD (P = 4.0 × 10^− 11) and MI (P = 6.5 × 10^− 12) in GeneQuest with odds ratios of 0.53 and 0.42, respectively. The results were replicated in the Italian cohort (P = 0.004, OR = 0.71). The sib-TDT analysis also showed significant association between the TCCGC haplotype and CAD in GeneQuest II (P = 0.001). These results suggest that a common LRP8 haplotype TCCGC confers a significant protective effect on the development of familial, early-onset CAD and/or MI.     

Linkage and Association Between CA Repeat Polymorphism of the TNFR2 Gene and Obesity Phenotypes in Two Independent Caucasian Populations

Previously, our group has reported a suggestive linkage evidence of 1p36 with body mass index (BMI) (LOD = 2.09). The tumor necrosis factor receptor 2 (TNFR2) at 1p36 is an excellent positional and functional candidate gene for obesity. In this study, we have investigated the linkage and association between the TNFR2 gene and obesity phenotypes in two large independent samples, using the quantitative transmission disequilibrium tests (QTDT). The first group was made up of 1 836 individuals from 79 multi-generation pedigrees. The second group was a randomly ascertained set of 636 individuals from 157 US Caucasian nuclear families. Obesity phenotypes tested include BMI, fat mass, and percentage fat mass (PFM). A significant result (P = 0.0056) was observed for linkage with BMI in the sample of the multigenerational pedigrees. Our data support the TNFR2 gene as a quantitative trait locus (QTL) underlying BMI variation in the Caucasian populations.     

eNOS基因第四内含子a／b多态与湖北汉族人原发性高血压而不是2型糖尿病相关联

目的：探讨内皮型一氧化氮合酶基因（eNOS）与湖北汉族人原发性高血压（EH）和2型糖尿病（T2DM）的关系。方法：采用病例-对照设计,分析了657例样本eNOS第四内含子重复序列多态性a／b,测量了身高、体重、腰围、臀围、收缩压、舒张压、空腹血糖,餐后2小时血糖等临床指标。结果：EH病例组eNOSab＋aa基因型和a等位基因频率显著高于EH对照组（基因型：25．3％vs18．9％,P=0．049;等位基因：13．3％vs9．8％,P=0．045）;而T2DM病例组与T2DM对照组的eNOSab＋aa基因型频率没有显著差异（20．2％vs24．1％,P=0．247）。单因素Logistic回归分析显示eNOSab＋aa基因型是EH的危险因子（OR=1．623,95％CI 1．053—2．506,P=0．029）。多因素回归分析显示,EH的独立风险因素是年龄、体重指数和eNOS基因a／b多态性,而体重指数和腰臀比是T2DM的独立风险因素。结论：eNOS基因a／b多态性是湖北汉族人群EH的一个易感标记,而与T2DM没有相关性。     

Genetic variation rs10484761 on 6p21.1 derived from a genome-wide association study is associated with gastric cancer survival in a Chinese population

A recent genome-wide association study (GWAS) on esophageal squamous-cell carcinoma (ESCC) among Chinese people has discovered a novel single nucleotide polymorphism (SNP) rs10484761 on 6p21.1 region. We hypothesized that SNP rs10484761 T/C is associated with survival of gastric cancer. We genotyped SNP rs10484761 in 940 gastric cancer patients treated with surgical resection. Kaplan–Meier survival analysis, log-rank test, and Cox proportional hazard models were used to evaluate the association between the SNP rs10484761 and gastric cancer survival. In the dominant model, those who carry TC/CC genotypes had a significant shorter survival time (log-rank P = 0.005), especially in the subgroups of aged male patients, cardia intestinal tumor (HR = 1.41, 95% CI = 1.08–1.84 for cardia cancer and HR = 1.64, 95% CI = 1.14–2.37 for intestinal-type), tumor size ≤ 5 cm (HR = 1.41, 95% CI = 0.56–0.99), T1 depth invasion (HR = 2.34, 95% CI = 1.20–4.56), lymph node metastasis (HR = 1.51, 95% CI = 1.19–1.96), no distant metastasis (HR = 1.33, 95% CI = 1.05–1.68), TNM stage III + IV (HR = 1.50, 95% CI = 1.13–1.98), and with chemotherapy (HR = 1.53, 95% CI = 1.17–1.99). The results indicated that SNP rs10484761 was associated with prognosis of gastric cancer, suggesting that this genetic variant may serve as a potential marker to predict the survival of gastric cancer in Chinese population.     

Genetic polymorphisms of IFNG and IFNGR1 in association with the risk of pulmonary tuberculosis

Objective

Genetic host factors play an important role in controlling individual's susceptibility to the pathogen. This study aims to explore the single and joint effect of genetic polymorphisms of interferon-gamma (IFNG) and its receptor (IFNGR1) in association with the pulmonary tuberculosis in a Chinese Han population.

Methods

This population-based case control study consisted of 1434 pulmonary tuberculosis patients and 1412 healthy controls. Six tag SNPs in IFNG/IFNGR1 were genotyped using TaqMan allelic discrimination technology. The logistic regression model was carried out to analyze the associations between the genotypes and haplotypes and the risk of tuberculosis by calculating the odds ratio (OR) and 95% confidence interval (CI).

Results

After the Bonferroni correction for multiple comparisons, three SNPs (rs2234711, rs1327475 and rs7749390) in IFNGR1 gene were observed to be significantly associated with the altered risks of tuberculosis. For the SNP rs2234711, individuals carrying C allele (vs. T) showed a decreased risk, with the adjusted OR(95% CI) of 0.82(0.76–0.91). The additive model revealed that each additional allele contributed about 14% decreased risk (OR: 0.86, 95% CI: 0.77–0.95). Moreover, we observed a strong linkage disequilibrium between rs2234711 and rs3799488. Compared with the common rs2234711C–rs3799488C haplotype, the haplotype rs2234711T–rs3799488C contributed to a significant increase in the risk of tuberculosis (adjusted OR: 1.24, 95% CI: 1.09–1.41).

Conclusions

Our results suggest that genetic polymorphisms in IFNGR1 gene are involved in the risk of tuberculosis in the Chinese population. Future studies should include a comprehensive sequencing analysis to identify the specific causative sequence variants underlying the observed associations.     

Genetic variations in VDR associated with prostate cancer risk and progression in a Korean population

Low levels of vitamin D are implicated as a potential risk factor for prostate cancer, and the vitamin D receptor (VDR) gene may be important in the onset and progression of prostate cancer. In this study, sequence variants in the VDR gene were investigated in a Korean study cohort to determine whether they are associated with prostate cancer risk. We evaluated the association between 47 single nucleotide polymorphisms (SNPs) in the VDR gene and prostate cancer risk as well as clinical characteristics (prostate-specific antigen level, clinical stage, pathological stage and Gleason score) in Korean men (272 prostate cancer patients and 173 benign prostatic hyperplasia patient who underwent a prostate biopsy, which was negative for malignancy) using unconditional logistic regression. The statistical analysis suggested that two VDR sequence variants (rs2408876 and rs2239182) had a significant association with prostate cancer risk (odds ratio [OR]. 1.41; p = 0.03; OR, 0.73; p = 0.05, respectively). Logistic analyses of the VDR polymorphisms with several prostate cancer related factors showed that several SNPs were significant; nine SNPs to PSA level, three to clinical stage, two to pathological stage, and three SNPs to the Gleason score. The results suggest that some VDR gene polymorphisms in Korean men might not only be associated with prostate cancer risk but also significantly related to prostate cancer-related risk factors such as PSA level, tumor stage, and Gleason score. However, current limitation for small cohort with not-healthy control group might have false positive effects; therefore it should be overcome via further large-scale validating studies.     

Genetic variants in BMP8B gene are associated with growth traits in Chinese native cattle

As a signaling molecule, bone morphogenetic protein 8B (BMP8B) plays an essential role in bone metabolism and is able to regulate thermogenesis and energy balance, which suggests that BMP8B gene may be a new candidate for growth traits. Here, to characterize the effects of BMP8B gene on growth traits, we first used three Chinese indigenous cattle breeds (n = 845) to detect single nucleotide polymorphisms (SNPs). Five novel SNPs of BMP8B gene (g.− 242C>T, g.2164C>T, g.2639T>C, g.2900C>G and g.10817C>T) were identified by DNA pool sequencing and forced PCR–RFLP. And then we associated the five SNPs with four growth traits (body weight, body length, heart girth, and hucklebone width). Results from association analysis showed that the SNPs 1, 2, and 3 affected growth trait(s) markedly (P < 0.05). Further, 6 combined haplotypes were constructed to guarantee the reliability of analysis results. There were also significant differences in body length, heart girth and body weight between the 6 combined haplotypes (P < 0.05), but not in hucklebone width (P > 0.05). Collectively, our results suggest a modulatory role of BMP8B gene in cattle growth and development, and 3 SNPs could be used as molecular markers in early marker assisted selection (MAS) in beef cattle breeding program.     

Association of the + 45T > G adiponectin gene polymorphism with insulin resistance in non-diabetic Saudi women

Background

The human adiponectin gene variations are associated with obesity, insulin resistance, and diabetes. However, these associations have not been fully examined in a non-diabetic population in Saudi Arabia. We aimed to investigate the association of 45T > G single nucleotide polymorphism (SNP) in the adiponectin gene with total adiponectin levels, insulin resistance (IR), fasting blood glucose (FBG) and other markers of obesity in non-diabetic Saudi females.

Methods

One hundred non diabetic Saudi females were enrolled in this study. They were further divided according to their body mass index (BMI) into two groups. Group I, 46 non diabetic subjects with normal body weight and group II, 54 overweight and obese females. Adiponectin 45T/G polymorphism was detected by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP). Serum adiponectin was measured by ELISA.

Results

Obese women exhibited a higher distribution of TG/GG genotype compared with non-obese women. SNP + 45T > G genotypes were associated with higher FBG, insulin levels and HOMA–IR with lower total adiponectin levels in obese Saudi women. Otherwise the all estimated variables revealed non-significant differences among the non-obese genotypes. The observed differences in insulin resistance markers were very significant among women with a higher body weight but not among normal body weight women, thus suggesting that SNP + 45T > G effects on insulin sensitivity may depend upon body weight and body fat status.

Conclusion

SNP + 45T > G of adiponectin gene has a significant role in the development of insulin resistance in Saudi women possibly through an interaction with increase body weight and hypoadiponectinemia.     

miR-27a suppresses triglyceride accumulation and affects gene mRNA expression associated with fat metabolism in dairy goat mammary gland epithelial cells

MicroRNAs (miRNAs), a well-defined group of small RNAs containing about 22 nucleotides, participate in various biological metabolic processes. miR-27a is a miRNA that is known to regulate fat synthesis and differentiation in preadipocyte cells. However, little is known regarding the role that miR-27a plays in regulating goat milk fat synthesis. In this study, we determined the miR-27a expression profile in goat mammary gland and found that miR-27a expression was correlated with the lactation cycle. Additionally, prolactin promoted miR-27a expression in goat mammary gland epithelial cells. Further functional analysis showed that over-expression of miR-27a down-regulated triglyceride accumulation and decreased the ratio of unsaturated/saturated fatty acid in mammary gland epithelial cells. miR-27a also significantly affected mRNA expression related to milk fat metabolism. Specifically, over-expression of miR-27a reduced gene mRNA expression associated with triglyceride synthesis by suppressing PPARγ protein levels. This study provides the first experimental evidence that miR-27a regulates triglyceride synthesis in goat mammary gland epithelial cells and improves our understanding about the importance of miRNAs in milk fat synthesis.