全基因组关联分析显示基因ANXA8和C10orf11为影响肌少症的候选基因

为了寻找与瘦体重(lean body mass,LBM)相关的单核苷酸多态性(single nucleotide polymorphism, SNP)位点及易感基因,在1 000个不相关的白人中采用Affymetix 500K芯片扫描了500 000个SNPs,并进行全基因组关联分析(genome-wide association study,GWAS),显著结果在1 625个中国人样本和2 283个欧洲白人样本中进行验证,并将验证结果与研究结果进行荟萃分析。研究发现SNPsrs7905603,rs9416083,rs4409772,rs2894310与LBM关联,其中rs7905603位于基因ANXA8,其他3个SNPs位于基因C10orf11。荟萃分析得到的合并p值分别为2.08×10-5,7.44×10~(-6),6.73×10~(-6),6.76×10~(-6)。ANXA8和C10orf11基因是影响LBM变异的候选基因,这对肌少症的认识提供了新的理论依据。     

白杨派,青杨派和黑杨派的DNA多态性及系统进化研究

收集了杨属三个派内２０个种的２８个无性系，筛选７个引物进行ＲＡＰＤ分析。共产生５４条有效谱带，其中４３条（７９．６３％）表现多态性。任意两无性系间的遗传距离（Ｄ）为０．９３０￣０．０３１，相应其相似性为０．５１８￣０．９７０。以Ｄ值为基础研究三个派的系统进化关系，聚类结果表明三个派明显独立，且青杨派与黑杨派关系较近，而与白杨派则相对较远，结合其它研究成果推测白杨派较早从杨属中分离出来，而青杨派和黑     

7个水稻光温敏核不育系品种(系)的RAPD多态性分析

利用RAPD技术，从60个随机引物(10bp)中落选出了31个引物，能在供试的7个水稻光温敏核不育系不同品种(系)间扩增出180条稳定性较好的多态性片段．聚类分析结果显示，7个水稻光温敏核不育系品种(系)明量地聚为三类，其中同属于株1S体细胞诱变来的SV5，SVl0发生了较大的变异，相似系数均小于0．470，而SVl和SVl4变异较小，相似系数均大于0．890．H155与杂交亲本培矮64S的遗传差异较小，与杂交亲本株1S的遗传差异较大．该结果与田间农艺性状相符：另外，从7个水稻光温敏核不育系品种(系)的整体来看，相似系数均较大，说明遗传差异较小，遗传背景单一，从而在很大程度上限制了水稻杂种化势的利用．     

混合型高脂血症患者脂蛋白脂酶基因S447X的多态性

目的:研究中国人混合型高脂血症患者脂蛋白脂酶基因多态性.方法:应用聚合酶链反应(PCR)扩增114例混合型高脂血症患者LPL基因外显子9片段,采用低离子浓度-单链DNA构象多态性方法(LIS-SSCP),结合RFLP技术,进行筛查.结果:检测到S447X多态性.114例患者中,野生型100例,突变体杂合子12例,纯合子2例.结论:中国人中存在S447X多态性,在所研究的混合型高脂血症患者中,与脂质水平无关联.     

Integration of rolling circle amplification and cationic conjugated polymer for the homogeneous detection of single nucleotide polymorphisms

A novel, homogeneous and sensitive assay for the detection of single nucleotide polymorphisms (SNPs) by integration of rolling circle amplification (RCA) and cationic conjugated polymer (CCP) has been developed and tested. Mutant DNA serves as the template for specifically circularizing a padlock probe (PLP) with a sequence that is complementary to the mutant DNA. Afterwards, the mutant DNA directly acts as the primer to initiate the RCA reaction in the presence of phi29 DNA polymerase that generates a long, tandem single-strand DNA product. During the RCA reaction, fluorescein-labeled dUTPs are incorporated into the RCA products. When the CCP is introduced, efficient FRET from CCP to fluorescein occurs as a result of the strong electrostatic interactions between the CCP and the DNA produced by RCA. The wild-type DNA contains a single base mismatch with PLP with the result that the PLP is not circularized, RCA is not triggered and inefficient FRET results. By measuring the change of the emission intensities of CCP and fluorescein, it was possible to detect the SNP in a homogeneous manner. The method is sensitive and specific enough to detect 0.1 pmol/L mutant DNA and to determine a mutant allele frequency as low as 2.0%.     

大仓鼠种群生境片断化的遗传效应研究

利用原仓鼠微卫星引物扩增曲阜吴村、平邑柏林和卞桥三个地理种群的大仓鼠基因组DNA,并对长约550bp的特异片段回收测序,利用DAMBE、DNASP4．10及MEGA3．0软件分析所得序列．结果表明,在三个地理种群内及种群间均检测到不同数目的SNPs存在,种群内多态信息含量表现为柏林〉吴村〉卞桥．种群间则以曲阜吴村和平邑卞桥间含量最高．在被检测序列496bp中共检测到6个信息位点,其中4个转换、2个颠换;以平邑柏林和卞桥间含量最低,仅检测到2个信息位点且均为转换．三个地理种群的遗传分化系数（Gst）平均约为0．18,产生的基因流Nm为1．03-1．18,该结果揭示由于生境片断化导致的不同地理种群之间基因流的降低,将会对种群间的遗传分化产生重要的作用．     

Immunological determinants of the outcomes from primary hepatitis C infection

Individuals infected with hepatitis C virus (HCV) have two possible outcomes of infection, clearance or persistent infection, determined by a complex set of virus-host interactions. The focus of this review is the host mechanisms that facilitate clearance. Strong evidence points to characteristics of the cellular immune response as the key determinants of outcome, with evidence for the coordinated effects of the timing, magnitude, and breadth, as well as the intra-hepatic localisation of CD4+ and CD8+ T cell responses being critical. The recent discovery of viral evasion strategies targeting innate immunity suggests that interferon-stimulated gene products are also important. A growing body of evidence has implicated polymorphisms in both innate and adaptive immune response genes as determinants of viral clearance in individuals with acute HCV. Received 16 May 2008; received after revision 07 September 2008; accepted 30 September 2008     

血管舒缓素基因D19S246重复序列多态性与新疆哈萨克族原发性高血压

探讨了血管舒缓素(kallikrein,KLK)基因D19S246重复序列多态性与原发性高血压(essential hypertension,EH)的关系。应用PCR扩增、毛细管电泳和Genetic Profiler自动分析软件进行微卫星基因组扫描分析,选取新疆哈萨克族EH患者196例,正常血压者94例,检测KLK基因D19S246重复序列多态性。KLK基因D19S246重复序列存在11种等位基因,分布符合Hardy-Weinberg平衡,扩增片段长度为205 bp的A6等位基因最常见。该位点杂合度为0.813,多态信息量为0.809。D19S246重复序列多态性在哈萨克族EH组和对照组的分布无显著差异(χ2=9.097,P=0.523)。结果显示KLK基因D19S246重复序列多态性可能与哈萨克族EH不相关。     

NPY基因SNPs与鸡屠体性状的关联分析

利用PCR-SSCP法对AA肉鸡、仙居鸡(兼用型)和罗曼蛋鸡神经肽Y(NPY)基因全序列进行了单核苷酸多态(SNPs)检测.在基因内含子2中发现了5个紧密连锁的碱基变异位点:T2623C,C2704T,T2776G,T2787C和A2821G,这5个位点以单倍型的方式在突变基因型个体中遗传;各品种间NPY 基因AA野生型、AB杂合型和BB突变型基因及基因型频率分布差异极显著(P<0.01);基因型对鸡腹脂率、腿肌率及肝重有显著影响,BB基因型个体的腹脂率、腿肌率显著高于AA型和AB型,AB型个体的肝重显著高于AA型和BB型.因此,NPY基因可能是影响鸡脂肪沉积和屠体性状的主效基因或与主效基因相连锁.