比较染色体涂色显示小熊猫(Ailurus fulgens)具有高度保守的核型

以狗的整条染色体特异探针,通过比较染色体涂色(Comparative Chromosome Painting),建立了小熊猫和狗的比较染色体图谱。狗的38条常染色体探针在小熊猫染色体上共检出71个同源片段。其中狗的18条常染色体每一条在小熊猫染色体上各有1个同源片段,其余的20条常染色体每一条在小熊猫染色体上各有2至5个同源片段。广泛的染色体结构重排造成了小熊猫与狗的核型差异:至少需要经过28次断裂,49次融合,4次倒位才能将狗的核型(2n =78)“转变”为小熊猫的核型(2n =36)。

云南不同地区绵羊血液蛋白多态性研究

本研究采用平板式淀粉胶蛋白电泳技术对来自德钦县、巧家县、腾冲县的绵羊进行了 34个同功酶及血液蛋白的研究 ,共检测 36个遗传座位 ,其中有 8个座位显示多态 ,德钦绵羊多态百分率P =0 .194 4 ,平均杂合度H =0 .0 6 4 7,平均等位基因数A =1.2 2 2 2 ;昭通绵羊P =0 .2 2 2 2 ,H =0 .0 6 5 1;A =1.2 2 2 2 ;腾冲绵羊P =0 .16 6 7,H =0 .0 6 0 8;A =1.16 6 7。表明云南不同地区绵羊在蛋白水平上遗传多样性较为丰富。运用Phylip3.5软件包中的”GENETDIST”计算标准遗传距离 ,再结合以往研究的数据 ,运用该软件包中的”NEIGHBOR”和”UPGMA”法进行聚类分析 ,结果表明 ,云南绵羊起源于同一共同祖先 ,云南绵羊与印度绵羊、尼泊尔绵羊关系较近 ,而与西藏绵羊关系较远

羚牛细胞色素J基因序列分析和系统进化研究

C应用聚合酶链式反应’NOP(分别扩增了羚牛Q绵羊Q山羊Q黄牛细胞色素R基因H并对其全序 列’##&"RS(进行了测定I其中羚牛细胞色素R基因序列属首次报道I通过对$种偶蹄类动物细胞 色素R基因序列差异分析和基于序列差异所构建的分子系统树H发现羚牛与羊亚科的动物亲缘关 系最近H与其他动物亲缘关系较远H表明将羚牛放入羊亚科较为合理I序列差异分析还表明羚牛约 在距今G""万年前’上新世(从牛类动物中分化出来H牛类分化时间约在L""万年前的中新世 ’T8*<5-5(

麻栗坡县家马mtDNA多态性研究

对采自麻栗坡县的晋通马矮马各３匹的材料，所用２０种限制性内切酶中，有１６种可产生切点，平均每个个体获得５６条限制性片段。与其它家畜家一不同，家马有高度的ｍｔＤＮＡ多态性，６匹马均有自己独特的ｍｔＤ－ＮＡ基因型，提示该地家马可能为多起源，至少有多重母系，这些母系可追溯到１～１０万年前，与化石记载相一致。本次实验未找到将两种马区分开的特异性多态标记，这可能是同栖于同一生态环境中，相互交配，血液相融，而不是各自起源于自己原母系。由于所测样本数较少，尚不能得到区分两种马的一个统计学上的规律性来。云南地理地貌十分复杂，马的品种或类群较多，亦可能是多起源，其遗传多样性很丰富。因此，云南马是值得保护和重视的种质资源库。自８０年代以来，动物线粒体ＤＮＡ（ｍｔＤ－ＮＡ）在群体遗传及进化生物学研究中起着重要作用，由于其组成序列简单，母体遗传，且不存在重组，所以是追踪母系血统的理想标记和能对漂移血统进行识别￣［１］（Ｈａｒｒｉｓｏｎｌ９８９年）．在家养动物中，对ｍｔＤＮＡ多态性研究以前多在鸡、黄牛、猪中进行，它们的ｍｔＤＮＡ多态频率相当低￣［２］。Ｍａｒｔｈｅｗ和Ｒｙｄｅｒ（１９８６）的研究已涉及家马ｍｔＤＮＡ种内特异性的情况.

THE CHROMOSOMES OF TUFTED DEER (ELAPHODUS-CEPHALOPHUS)

Mitotic and meiotic chromosome preparations of the tufted deer (Elaphodus cephalophus) were studied to elucidate the sex-chromosomal polymorphism evidenced by this species. Females had 2n = 46 or 47 chromosomes, whereas males had 2n = 47 or 48 chromosomes. An X;autosome translocation was identified by synaptonemal complex analysis of spermatocytes at pachytene and confirmed by the presence of a trivalent at diakinesis/metaphase I. The present work, in combination with earlier observations by others, indicates that E. cephalophus possesses a varied X-chromosome morphology involving an X;autosome translocation and addition of varying amounts of heterochromatin. It is speculated that sex-chromosome polymorphism may be responsible for the observed differences in diploid chromosome number of tufted deer.

A COMPARATIVE-STUDY OF KARYOTYPES OF MUNTJACS BY CHROMOSOME PAINTING

We have used a combination of chromosome sorting, degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR), chromosome painting and digital image capturing and processing techniques for comparative chromosome analysis of members of the genus Muntiacus. Chromosome-specific ''paints'' from a female Indian muntjac were hybridised to the metaphase chromosomes of the Gongshan, Black, and Chinese muntjac by both single and three colour chromosome painting. Karyotypes and idiograms for the Indian, Gongshan, Black and Chinese muntjac were constructed, based on enhanced 4', 6-diamidino-2-phenylindole (DAPI) banding patterns. The hybridisation signal for each paint was assigned to specific bands or chromosomes for all of the above muntjac species. The interspecific chromosomal homology was demonstrated by the use of both enhanced DAPI banding and comparative chromosome painting. These results provide direct molecular cytogenetic evidence for the tandem fusion theory of the chromosome evolution of muntjac species.

我国西南地区珍稀濒危动物的进化和保护遗传学研究

中国西南地区分布有许多重要的珍稀濒危动物，对它们的保护举世瞩目，其中一些动物的分类进化地位还存在着争议。我们实验室多年来致力于这些物种的进化遗传和保护遗传学研究，旨在阐明这些物种的进化地位，确定野生或圈养群体的遗传结构，为制定科学的保护计划提供不可缺少的遗传学资料。

云南矮马资源及种质研究总结

矮马在国内重新发现后，我们对云南矮马历经７年的调查研究，取得如下主要结果：（１）据史料记述，考古物证，血液蛋白多态测定，云南极可能是矮马渊源地；（２）对全省１２个地（州）实地调查及５个地（州）的了解，证明云南全省均有矮马，其数量占全国矮马总数的８５％～９０％，表明云南为矮马的中心产区。矮马的分布密度与生态环境、社会经济、文化、交通状况密切相关，与海拔、气温关系不大；（３）对正常的成年矮马和普通马，屠测６９项指标，其差异达显著和极显著水平的占５２．２７％；（４）对头骨形态和１０５项尺度观测，两种马间差异达显著和极显著水准的占７２．３８％，表明二者为独立的品种。通过臼齿大小及齿面雏褶形态鉴别，两者间存在明显差异，并确认两种马均为古老品种；（５）测定矮马、普通马的血液生理生化指标２８项４６个指标，有７个指标存在显著和极显著差异。（６）两种马的染色体数均为２ｎ＝６４，Ｃ带结构异染色质存在明显差异，反映出两种马间遗传进化上的差异；（７）对矮马、普通马的６种血液蛋白和同功酶测定，测到９个多态位点，结果在ＴＦ上两者有明显差异。对矮马、普通马样本，测定４４个遗传座位，１０个多态遗传座位中ＰＧＭ及ＴＦ在两品种间差异显著.

Evolution of the black muntjac (Muntiacus crinifrons) karyotype revealed by comparative chromosome painting

The black muntjac (Muntiacus crinifrons) has an unusual karyotype of 2n = 8 in females and 2n = 9 in males. We have studied the evolution of this karyotype by hybridising chromosome-specific paints derived from flow-sorted chromosomes of the Chinese muntjac (M. reevesi, 2n = 46) to chromosomes of the black muntjac. The hybridisation pattern allowed us to infer chromosomal homologies between these two species. Tandem and centromeric fusions, reciprocal translocations, and insertions are involved in the reduction of the diploid number from 2n = 46 to 2n = 8, 9. The painting patterns further show complex chromosomal rearrangements in the male black muntjac which involve more than half the karyotype, including both sex chromosomes. Since early meiosis is reported to be normal without any visible inversion loops of the synaptonemal complex, the observed chromosomal rearrangements would lead to heterosynapsis and, therefore, leave a large fraction of the male black muntjac karyotype balanced between the two sexes.

云南两个地方鸡种血液蛋白多态性研究

本试验采用水平式淀粉凝胶电泳法，对版纳斗鸡、武定鸡的６０个样本，３２个遗传位点的血液蛋白多态性进行了检测。这两个品种只在ＥＳ－１、ＡＫｐ－１、ＡＫｐ－２、ＬＡＰ四个座位显示多态。其余２５个位点均为单态，尚有ＣＰ、ＸＤＨ和ＩＤＨ三个座位染色后未出现谱带。试验结果表明：两鸡种之间虽呈现一定的遗传差异，但平均基因杂合度较小（０．０６０７；０．０６４８），两者间遗传距离较近（０．０７７８）。

Mapping chromosomal homologies between humans and two langurs (Semnopithecus francoisi and S-Phayrei) by chromosome painting

Chromosomal homologies were established between human and two Chinese langurs (Semnopithecus francoisi, 2n=44, and S. phayrei, 2n=44) by chromosome painting with chromosome-specific DNA probes of all human chromosomes except the Y. Both langur species showed identical hybridization patterns in addition to similar G-banding patterns. In total, 23 human chromosome-specific probes detected 30 homologous chromosome segments in a haploid langur genome. Except for human chromosomes 1, 2, 6, 16 and 19 probes, which each gave signals on two non-homologous langur chromosomes respectively, all other probes each hybridized to a single chromosome. The results indicate a high degree of conservation of chromosomal synteny between human and these two Chinese langurs. The human chromosome 2 probe painted the entire euchromatic regions of langur chromosomes 14 and 19. Human chromosome 1 probe hybridized to three regions on langur autosomes, one region on langur chromosome 4 and two regions on langur chromosome 5. Human 19 probe hybridized on the same pattern to one region on chromosome 4 and to two regions on langur chromosome 5, where it alternated with the human chromosome 1 probe. Human 6 and 16 probes both hybridized to one region on each of the two langur autosomes 15 and 18. Only two langur chromosomes (12 and 21) were each labelled by probes specific for two whole human chromosomes (14 and 15 and 21 and 22 respectively). Comparison of the hybridization patterns of human painting probes on these two langurs with the data on other Old World primates suggests that reciprocal and Robertsonian translocations as will as inversions could have occurred since the divergance of human and the langurs from a common ancestor. This comparison also indicates that Asian colobines are karyotypically more closely related to each other that to African colobines.

云南保种山羊血液同工酶遗传多样性研究

采用水平式淀粉胶电泳技术 ,对云南龙陵黄山羊、宁蒗黑头山羊、马关无角山羊和路南圭山羊等 4个保种山羊的 1 2 0个个体共 3 9个基因座位的基因多态性进行了研究。结果显示 ,云南 4个保种山羊品种在AKP、CES - 1、ESD、GOI、LAP、MDH、ME和NP基因座位出现多态。多态座位基因在不同保种山羊中分布不同。多态基因座位百分比 (P)在 4个保种山羊中分别为 0 .2 0 51 ,0 .1 53 8,0 .1 2 82和 0 .1 53 8。平均杂合度 (H)分别为 0 .0 95,0 .0 61 4 ,0 .0 4 67和 0 .0 662。用UPGMA法对由基因频率计算得到的Nei氏标准遗传距离进行聚类分析 ,结果表明云南保种山羊具地理分布及品种特点 ,龙陵黄山羊和其它 3个品种的遗传距离最远。

Reciprocal chromosome painting illuminates the history of genome evolution of the domestic cat, dog and human

Domestic cats and dogs are important companion animals and model animals in biomedical research. The cat has a highly conserved karyotype, closely resembling the ancestral karyotype of mammals, while the dog has one of the most extensively rearranged mammalian karyotypes investigated so far. We have constructed the first detailed comparative chromosome map of the domestic dog and cat by reciprocal chromosome painting. Dog paints specific for the 38 autosomes and the X chromosomes delineated 68 conserved chromosomal segments in the cat, while reverse painting of cat probes onto red fox and dog chromosomes revealed 65 conserved segments. Most conserved segments on cat chromosomes also show a high degree of conservation in G-banding patterns compared with their canine counterparts. At least 47 chromosomal fissions (breaks), 25 fusions and one inversion are needed to convert the cat karyotype to that of the dog, confirming that extensive chromosome rearrangements differentiate the karyotypes of the cat and dog. Comparative analysis of the distribution patterns of conserved segments defined by dog paints on cat and human chromosomes has refined the human/cat comparative genome map and, most importantly, has revealed 15 cryptic inversions in seven large chromosomal regions of conserved synteny between humans and cats.

滇金丝猴的随机扩增多态DNA与遗传多样性分析

对6只笼养滇金丝猴(Rhinopithecus bieti)进行了随机扩增多态DNA(RAPD)及遗传多样性分析.用45个10bp随机短引物对每只滇金丝猴的基因组DNA进行了扩增,平均每个个体观察到的RAPD标记约为130个左右,单个引物获得的标记在1～7个之间.80%的RAPD标记表现为无多态的单型性.个体间的遗传距离为0.052,表明笼养滇金丝猴群体的遗传多样性很低.此研究结果与在蛋白多态研究中得到的一致.贫乏的遗传多样性一方面使目前处于濒危境地的滇金丝猴生存情况更加危险,同时其本身也可能是造成目前滇金丝猴濒危的原因之一.另外,通过成对的遗传距离分析,构建了这一群滇金丝猴的谱系关系图,提出了让遗传距离较远的个体间进行交配的笼养繁育计划.

Dog chromosome-specific paints reveal evolutionary inter- and intrachromosomal rearrangements in the American mink and human

Forty chromosome-specific paint probes of the domestic dog (Canis familiaris, 2n = 78) were used to delineate conserved segments on metaphase chromosomes of the American mink (Mustela vison, 2n = 30) by fluorescence in situ hybridisation. Half of the 38 canine autosomal probes each painted one pair of homologous segments in a diploid mink metaphase, whereas the other 19 dog probes each painted from two to five pairs of discrete segments. In total, 38 canine autosomal paints highlighted 71 pairs of conserved segments in the mink. These painting results allow us to establish a complete comparative chromosome map between the American mink and domestic dog. This map demonstrates that extensive chromosome rearrangements differentiate the karyotypes of the dog and American mink. The 38 dog autosomes could be reconstructed from the 14 autosomes of the American mink through at least 47 fissions, 25 chromosome fusions, and six inversions. Furthermore, comparison of the current dog/mink map with the published human/dog map discloses 23 cryptic intrachromosomal rearrangements in 10 regions of conserved synteny in the human and American mink genomes and thus further refined the human/mink comparative genome map. Copyright (C) 2000 S. Karger AG, Basel.