中国及荷兰人群vWF基因内含子40多态性分析

本文调查了中国汉族及荷兰高加索群体中人类vWF基因内含子40 nt 31/2 215～2 380 区域 HUMFA 31(C) 遗传多态性的基因频率及基因型频率分布。并对两群体之间的分布以拟然比方法进行比较。对9个等位基因片段测序的结果表明, 在nt 31/2 234～2 265区域也有变异存在。提示该座位当被测等位基因DNA片段长度相同时,仍可能存在遗传差异。 Abstract　The allele frequencies and phenotype distribution of humanvWFgene intron 40 in the region of nt 31/2 215～2 380 (HUMFA 31(C)) were investigated in the population of the Netherlands and China. The data between two populations were compared by likelihood ratio test. Nine alleles were sequenced and the polymorphism of region of nt 31/2 234～2 265 was revealed.     

微卫星座位对实验动物beagle犬的遗传分析

目的对美国进口、广州自养beagle犬基因组中存在的微卫星结构进行分析,研究其群体的微卫星多态性,以此探索在分子水平上对作为实验动物的beagle犬进行检测。方法通过微卫星分子标记技术进行遗传背景分析,并结合微卫星位点测序结果,研究DNA分子特征。结果在研究位点上共发现6个复等位基因,进口犬群体共有6个等位基因片段,自养犬群体共有5个等位基因片段,根据基因型计算各群体等位基因频率,由相关公式计算杂合度、群体多态信息含量(PIC)、基因纯合率、基因分化系数。结论两群体的杂合度、PIC值均较高(分别为0.7010、0.6747和0.7876、0.7515),基因分化系数很低(0.021),表明两群体没有形成明显的独立群。     

利用回交B1和B2及F2群体鉴定数量性状两对主基因+多基因混合遗传模型

ＱＴＬ作图和主基因＋多基因混合遗传分析表明：拓展两对基基因＋多基因混合遗传模型十分必要。本文利用混合分布理论,ＡＩＣ准则在回交Ｂ１和Ｂ２群体或Ｆ２群体中鉴定两对主基因的存在,当主基因存在时估计其遗传参数;同时还改进了利用亲本,Ｆ１和回交Ｂ１和Ｂ２群体,或亲本,Ｆ１和Ｆ２群体鉴定多基因存在的方法,分布参数的估计采用ＩＥＣＭ算法,以水稻株高性状为例说明该方法的应用。     

中国南方汉族群体MPSⅠ型KpnⅠ酶切位点的遗传多态性

为研究中国汉族群体IDUA基因球KｐｎⅠ酶切位点的遗传多态性以及该位点等位基因片段传递的规律,采用PCR－RFLP技术,对162例无血缘关系的健康中国汉人的324条染色体进行检测,另又对5个家系16位成员进行同样的检测,然后用X2检验进行统计学处理。结果表明,等位基因A1频率为0．17,等位基因A2频率为0．83,杂合率为29％;A1、A2的传递规律与理论上预计的完全符合。认为中国汉族群体IDUA基因KｐｎⅠ酶切位点也具有遗传多态性,并且与国外报道的无显著性差异;A1、A2在世代中的传递完全符合孟德尔遗传规律。     

中国南方汉族群体MPSI型Kpn I酶切位点的遗传多态性

为研究中国汉族群体IDUA 基因Kpn I 酶切位点的遗传多态性以及该位点等位基因片段传递的规律, 采用PCR-RFLP技术, 对162例无血缘关系的健康中国汉人的324条 染色体进行检测,另又对5个家系16位成员进行同样的检测,然后用χ     

广东汉族人载脂蛋白B(apoB)基因3′端VNTR的遗传多态性研究

随机抽提100例无血缘关系的广东汉族人的血痕DNA,用PCR法扩增载脂蛋白B(apolipoprotein B apoB)基因3′端的VNTR,共检出19个等位基因,片段大小分布在510～1200bp之间,等位基因频率为0.005—0.195,杂合度为88.80％,父权排除率为0.6395,其等位基因数目及频率分布均与英国白种人的有差异。家系分析表明扩增片段按孟德尔方式遗传。本实验证实了apoB基因3′端VNTR的高度多态性和高度杂合性。     

广州汉族人群D12S391和D11S554基因座序列变异

为研究高度变异的sTR基因座核心序列结构,对广州汉族人群突变率较高的D12S391和D11S554基因座等位基因进行了序列分析。结果显示D12S391基因座核心序列结构为(AGAT)8～17(AGAC)6～10(AGAT)0～1,其较小片段等位基因(15～18)仅表现为第1个重复单位(AGAT)数目的变异,而较大片段等位基因(19～27),可表现为第2或第3个重复单位数目的变异。发现有4种新的等位基因,分别命名为22″、23″、24′″和27。D11S554基因座核心序列结构更复杂,有5种核心序列,其中3种具有相同的基本结构(AAAGG)(AAAG)4(AAAGG)2～3,(AAAG)13～19。其大片段等位基因(219～249)核心序列结构中,既有四核苷酸重复,还有五核苷酸重复,以及单个硷基的变异、硷基插入或缺失。两基因座均存在序列异质性。结果表明D12S391和D11S554基因座属复杂重复类型,为其准确分型增加了难度,首先需建立相应群体的等位基因分型标准物。     

HLA—DQ分子遗传结构与中国人重症肌无力的相关性

重症肌无力与ＨＬＡⅡ类基因关联性在不同人种和民族中具有不同遗传易感性,为探讨中国人重症肌无力（ＭＧ）与ＨＬＡ０ＤＱ分子关联性,采用聚合酶链式反应－限制性片段长度多态性（ＰＣＲ－ＲＦＬＰ）方法,分析了５０例中国正常人及４９例重症肌无力患者的ＨＬＡ－ＤＱＡ１和－ＤＱＢ１座位的基因型,结果：共检出正常人ＤＱＡ１等位基因８种,ＤＱＢ１等位基因１０种,重症肌无力患者ＤＱＡ１等位基因８种,ＤＱＢ１等位基因９种     

黄瓜花叶病毒亚组I和Ⅱ分离物外壳蛋白基因的序列分析与比较

对我国分离的经生物学和血清学鉴定为黄瓜花叶病毒（ＣＭＶ）亚组Ｉ和Ⅱ的各一分离物（ＧＢ、ＸＢ）的外壳蛋白（ＣＰ）基因进行了序列分析和比较。以提纯病毒ＲＮＡ为模板,进行逆转录及ＰＣＲ扩增,并通过常规基因克隆方法得到插入ＣＰ基因片段的重组克隆。对插入ＧＢ和ＸＢ两个分离物ＣＰ基因片段的重组克隆进行全序列测定,结果表明重组克隆序列长分别为７７７ｂｐ和７９２ｂｐ均只含一个开放读框（ＯＲＦ）,长度为６５７ｎｔ,     

应用ＣＡＴＳ法分离和鉴定猪ＧＦＡＰ基因的研究

根据比较锚定序列宗踪（ＣＡＴＳ）法,选择人和小鼠胶质细胞原纤维酸性蛋白（ＧＦＡＰ）基因的同源区域设计引,用ＰＣＲ方法从二花脸猪基因组中分离到４１２bp的基因片段,经与基因资料库中已训功能基因的同源性比较,该片段可鉴定为猪的ＧＦＡＰ基因,利用猪－啮齿类体细胞杂克隆板将ＧＦＡＰ基因定位于猪１２号染色体１２p11-(2/3)P13区域。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.