应用mtDNA COI基因序列鉴别常见嗜尸性蝇类种属

目的探讨mtDNA基因序列对常见嗜尸性蝇类的种属鉴别应用价值。方法收集不同区域2科4属6个种30个蝇类样本,提取样本线粒体DNA后扩增COI基因序列,以琼脂糖电泳检测扩增产物并测序,以DNAMAN6.0分析软件分别截取498bp序列,用MEGA5.2软件分别进行序列分析,然后构建系统发育树,比较各地区不同种属样本的序列差异。结果 6个种属的嗜尸性蝇类30个样本mtDNA的COI基因具有一定的序列差异,种内进化分歧均数在0.1%~1.6%之间,种间进化分歧均数在2.2%~11.2%之间,6个种属通过系统发育树均可明确区分。结论 COI基因序列分析和系统发育树对嗜尸性蝇类的种属检验具有重要帮助作用,可用于现场样本的准确、快速种属鉴定。     

应用mtDNA16S rRNA基因测序鉴定肉产品种属

目的 应用mtDNA 16S rRNA基因测序方法进行肉产品种属鉴定.方法 15份有关部门送检的未知动物肌肉样本,3份市购猪、牛和羊的肌肉为对照样本.常规酚-氯仿法提取模板DNA,分别用通用引物和特异性引物扩增mtDNA的16S rRNA基因片段,产物用1.5％琼脂糖电泳检测,扩增的基因片段由上海生物工程公司进行序列测...     

细胞色素b基因序列测定进行种属鉴定应用研究

目的建立细胞色素b基因序列测定进行种属鉴定的方法。方法应用特异性引物扩增人与14种常见动物细胞色素b基因14817～15174区间长度为358bp的片段,用荧光标记自动测序技术对此片段进行序列测定,比较这些动物与人之间片段的序列差异。结果所有血痕样本均可以得到良好的测序结果,所测14种动物细胞色素b基因358bp的片段序列与人之间均存在明显的差异,最小为20.1%,最大差异为28.5%。结论测定细胞色素b基因序列进行种属鉴定特异性强、适用检材广,具有良好的应用价值。     

mtDNA 12S rRNA基因序列测定在腐烂动物肌肉样本鉴定中的应用

目的利用mtDNA12SrRNA基因序列测定法对宁波森林公安局查获的一例腐烂动物肌肉样本进行种属鉴定,并探讨该方法在腐烂动物肌肉样本鉴定中的应用价值。方法用酚/氯仿法从腐烂动物肌肉样本中提取出基因组总DNA,再用一通用引物通过PCR技术扩增mtDNA上12SrRNA基因的部分片段并进行序列测定。测序结果在GenBank上进行BLAST搜索,再利用DNAMAN软件进行同源性分析。结果扩增产物序列与东北虎的线粒体DNA的12SrRNA基因序列的部分片段的同源性高达99.9%。结论该动物样本为东北虎,本研究所用方法在野生动物案件的样本鉴定中有极高的应用价值。     

线粒体16SrRNA和Cytb基因复合扩增进行种属鉴定

目的建立一种用于种属鉴定的线粒体DNA16SrRNA基因和细胞色素b基因荧光标记复合扩增检测体系。方法利用引物设计软件Primer5.0对mtDNA序列的16SrRNA基因和细胞色素b基因各设计一对引物,建立复合扩增体系,分别扩增人和牛、猪、狗、鸡、草鱼5种常见动物,用310遗传分析仪对产物进行分析。结果人和5种动物DNA扩增产物均出现两个峰,Cytb通用引物的扩增产物为人与动物的共有峰,为358bp;16SrRNA基因的扩增产物为人与动物间存在位置差异的特异峰,位于231～256bp之间。结论该复合扩增体系可以明确区分人和5种动物样本,可用于种属鉴定。     

线粒体16SrRNA和Cytb基因复合扩增进行种属鉴定

目的 建立一种用于种属鉴定的线粒体DNA16SrRNA基因和细胞色素b基因荧光标记复合扩增检测体系。方法 利用引物设计软件Primer 5．0对mtDNA序列的16SrRNA基因和细胞色素b基因各设计一对引物,建立复合扩增体系,分别扩增人和牛、猪、狗、鸡、草鱼5种常见动物,用310遗传分析仪对产物进行分析。结果 人和5种动物DNA扩增产物均出现两个峰。Cytb通用引物的扩增产物为人与动物的共有峰,为358bp;16SrRNA基因的扩增产物为人与动物间存在位置差异的特异峰,位于231～256bp之间。结论 该复合扩增体系可以明确区分人和5种动物样本,可用于种属鉴定。     

mtDNA—HVⅠ和细胞色素b片段的复合扩增及其法医学应用

目的探讨复合扩增mtDNA D环HV I和细胞色素b片段进行种属鉴定和个体识别的方法及mtDNA-HV I多态性。方法用两对引物同步扩增HV I片段与细胞色素b片段,银染显带检测扩增产物,ABI377测序仪及荧光测序技术分析扩增产物序列多态性。结果人类有279bp,358bp两条带,动物只有358bp一条带。通过对131例随机广东汉族人群个体进行mtDNA控制区(15997～16236))序列测定统计,得出此区域的序列多态性。共发现69个位点变异,平均每个个体存在2.679个碱基突变,检出67个单倍型,基因多样性为97.92％。结论mtDNA控制区(15997—16236)具有较高的序列多态性。为良好的个体识别标记。复合扩增mtDNA D环HV I与细胞色素b片段进行测序分析可以同步进行种属鉴定和个体识别。     

人和动物SON基因3’非编码区的PCR测序分析

目的 研究人和猕猴、阿拉伯狒狒、猪、牛、羊、马、驴、骡、狗、猫、兔、大白鼠、小白鼠、豚鼠等14种哺乳类动物SON基因3’非编码区(3’UTR)的种属特异性碱基序列差异。方法 对人和上述14种哺乳类的SON基因3’非编码区中的部分种属特异性区域进行PCR测序分析。结果 人有2条扩增片段和14种哺乳类动物各有1条扩增片段的碱基序列;人无关个体和同一种属不同个体动物DNA扩增片段的碱基序列相同,人、猕猴、阿拉伯狒狒、猪、牛、羊、马、驴、骡、狗、猫、兔、大白鼠、小白鼠、豚鼠DNA的SON基因3’UTR扩增片段之间存在碱基序列差异。结论 SON基因3’UTR是一个具有良好种属特异性的遗传标记,采用SON基因3’UTR扩增测序技术可以对人和上述14种哺乳类动物进行准确的种属鉴定。     

应用mtDNA 16S rRNA基因鉴定动物组织种属

目的应用线粒体DNA 16S rRNA基因PCR测序方法进行动物组织种属鉴定。方法未知动物内脏样本8份,已知马鹿、北山羊、绵羊和鹅喉羚肌肉样本各1份作为对照。采用用常规酚-氯仿法提取模板DNA,分别用哺乳动物通用引物和4种已知对照特异性引物扩增16S rRNA基因片段,产物用2.0%琼脂糖电泳检测,并进行序列测定及与基因库已有的序列同源性比对。结果 8份未知样本经哺乳动物16S rRNA通用引物扩增,均检测出阳性条带;用鹅喉羚特异性引物扩增,均检测出阳性特异性条带;用其他3种特异性引物扩增,均未检出阳性条带;未知样本扩增的基因片段经测序及同源性比对,与鹅喉羚的同源性为96%~100%。结论本文未知动物样本均为鹅喉羚内脏组织。本文方法可在动物检材种属鉴定中选用。     

线粒体16srRNA和ND4基因在种属鉴定中的应用研究

目的构建一种用于种属鉴定的线粒体DNA(m tDNA)16 srRNA和ND4基因荧光标记复合扩增检测体系。方法利用引物设计软件(Prim er 5)对两个m tDNA序列ND4基因和16 srRNA基因设计两对引物,每对引物中的一条在5’端标记荧光素(6-FAM)。按传统复合扩增技术建立复合扩增体系,用AB I PR ISM 310基因分析仪对产物进行分析。结果人类DNA扩增产物出现两个峰,片段大小分别为110bp的人类特异片段和149bp的人与动物共有片段,而动物DNA扩增产物出现一个峰,片段大小为149bp。对30个实验室存放5~15年的陈旧人血痕也能明确判断其种属来源。结论该体系可以明确区分人源性生物检材与其它常见动物样本,对实验室长期存放的陈旧检材也具有较好的检测能力。     

PCR-RFLP分析线粒体DNA细胞色素b基因用于法医学种属鉴定

目的建立一种PCR-RFLP分析线粒体DNAcyt b基因用于法医学种属鉴定的方法。方法采用一对通用引物扩增人及15种常见动物的线粒体DNAcyt b基因,扩增产物经内切酶Alu I酶切,分析不同动物DNA扩增产物的有无以及酶切前后的变化。结果所检动物中有9种DNA有扩增产物,经内切酶Alu I酶切后,除鳝鱼外都能与人类DNA相区别。结论PCR-RFLP分析线粒体DNAcyt b基因方法简单,结果可靠,是一种较好的法医学种属鉴定方法。     

Identification of DNA of human origin based on amplification of human-specific mitochondrial cytochrome b region

Species-specific differences in a non-polymorphic region of the mitochondrial cytochrome b gene appear to be large enough to allow human-specific amplification of forensic DNA samples. We therefore developed a PCR-based method using newly designed primers to amplify a 157-bp portion of the human mitochondrial cytochrome b gene. The forward and reverse primers were designed to hybridize to regions of the human mitochondrial cytochrome b gene with sequences differing from those of chimpanzee by 26% (7 bp/27 bp) and 26% (6 bp/23 bp), respectively. Using this primer pair, we successfully amplified DNA extracted from blood samples of 48 healthy adults. All these human samples produced a single band of the expected size on agarose gel electrophoresis, and the sequence of the single band was shown to be identical to that of the target region (157 bp) by sequence analysis. On the other hand, no visible bands were amplified from DNA extracted from blood samples of animals including non-human primates (chimpanzee, gorilla, Japanese monkey, crab-eating monkey) and other species (cow, pig, dog, goat, rat, chicken and tuna). Thus, DNA producing a single band following PCR amplification using this primer pair can be reasonably interpreted as being of human origin. In addition, aged biological specimens comprising bloodstains, hair shafts and bones were successfully identified as being of human origin, illustrating the applicability of the present method to forensic specimens.     

Cytochrome b gene for species identification of the conservation animals

A partial DNA sequence of cytochrome b gene was used to identify the remains of endangered animals and species endemic to Taiwan. The conservation of animals species included in this study were: the formosan gem-faced civets, leopard cats, tigers, clouded leopards, lion, formosan muntjacs, formosan sika deers, formosan sambars, formosan serows, water buffalo, formosan pangolins and formosan macaques. The control species used included domestic cats, domestic dogs, domestic sheeps, domestic cattles, domestic pigs and humans. Heteroplasmy was detected in the formosan macaque, domestic pig and domestic cats. The frequencies of heteroplasmy in these animals were about 0.25% (1 in 402bp). Sequences were aligned by Pileup program of GCG computer package, and the phylogenetic tree was constructed by the neighbor-joining method. The results of sequence comparison showed that the percentage range of sequence diversity in the same species was from 0.25 to 2.74%, and that between the different species was from 5.97 to 34.83%. The results of phylogenetic analysis showed that the genetic distance between the different species was from 6.33 to 40.59. Animals of the same species, both the endangered animal species and domestic animals, were clustered together in the neighbor-joining tree. Three unknown samples of animal remains were identified by this system. The partial sequence of cytochrome b gene adopted in this study proved to be usable for animal identification.     

Application of cytochrome b DNA sequences for the authentication of endangered snake species

In order to enforce the conservation program and curbing the illegal trading and consumption of endangered snake species, the value of cytochrome b sequence in the authentication of snake species was evaluated. As an illustration, DNA was extracted, selected cytochrome b DNA sequences amplified and sequenced from six snakes commonly consumed in Hong Kong. Cataloging with sequences available in public, a cytochrome b database containing 90 species of snakes was constructed. In this database, sequence homology between snakes ranged from 70.68 to 95.11%. On the other hand, intraspecific variation of three tested snakes was 0-0.98%. Using the database, we were able to determine the identity of six meat samples confiscated by the Agriculture, Fisheries and Conservation Department, HKSAR.     

Structural variations of the VWA locus in humans and comparison with non-human primates

The HUMVWA locus was examined in 160 samples from the Japanese population. A total of 142 fragments were sequenced, and the counterpart sequences were also determined in non-human primates. In humans, 10 different alleles were found; they could be grouped into seven allelic classes based on the total number of repeats. No variation was observed in the alleles 17, 18 and 19, which showed consensus sequence structures and in the allele 14, which showed a different structure. New variation was found in alleles 15, 16, and 20, which had differences occurred in a basic (TCTA)(TCTG)(n) repeat in the 5' side. The counterpart fragments were successfully amplified in three species (chimpanzees, gorilla, and orangutan) out of four kinds of anthropoids, three species (rhesus macaques, Japanese macaques, and green monkey) out of four kinds of old world monkeys, but not in one species of either new world monkey or prosimian. The sizes of the fragments distributed from 92 to 180 bp in non-human primates and showed allelic size differences in four species. The sequence of the 5' flanking region followed by primer sequences in humans and anthropoids, which consisted of 19 bp, was identical in all, but differed from that in old world monkeys. The basic repeat motifs of humans and anthropoids consisted of TCTA, TCTG, and TCCA but that of old world monkeys consisted of TCTG, TCCG and TCCA The structures of humans and anthropoids were essentially similar, but with characteristic difference in each species. Differences in the allelic structures of old world monkeys were complex. Seven different alleles were observed in two rhesus and two Japanese macaques and one type of allele was observed in two green monkeys. Duplication of more than two repeat units of 4 bp was found in an allele of an old world monkey. These data illuminate interesting features of mutational changes in STRs during the long generations and also some insight into evolutional aspects of primates.     

Nucleotide variability of HV-I in Afro-descendents populations of the Brazilian Amazon Region

The analysis of genetic variation in the nucleotide sequences of mitochondrial DNA, provides unique information about the population diversity and human identification. In this study, the mitochondrial DNA sequences of the first hypervariable region (HV-I) were analyzed in 243 unrelated individuals of seven Afro-descendents populations of the Amazon Region. Sequence polymorphisms were detected using PCR and direct sequencing analysis. A total of 133 different haplotypes were found determined by 97 variable nucleotides. Each one of the three more frequent haplotypes was shared by 9 samples and 91 sequences were unique. The genetic diversity was estimated to 0.9898+/-0.0016 and the probability of two random individuals showed identical mitochondrial DNA (mtDNA) haplotypes were 1.2%.     

20个STR基因座的种属特异性研究

确定本室常用的20个STR基因座对常见10种动物的种属特异性。20个STR基因座对10种常见动物血或软组织的DNA进行PCR扩增、聚丙烯酰胺凝胶电泳、银染色法进行DNA分型,测定各STR基因座的种属特异性。D11S554、SE33基因座对10种动物DNA,D12S391、CSF基因座对狒狒DNA,D19S253基因座对兔、狒狒的DNA,FGA基因座对兔、猴、狒狒的DNA均有PCR扩增产物,其片段长度与人的在同一电泳区内;DYS19基因座对10种动物的DNA,FES基因座对鸡DNA,PLA基因座对猪DNA,D21S11基因座对蛇、牛、狒狒的DNA有扩增产物,但其片段长度明显与人的不同。DYS389、DYS288、DYS390、D7S809、D13S631,TH01、vWA、AR、CD4、FABP基因座对鸡、猪等动物的DNA均无PCR扩增产物。在20个STR基因座中,10个基因座只对人DNA有扩增产物,有较好的种属特异性;8个基因座对人和部分动物均有扩增产物,但产物的片段大小与人的不同,在进行个人识别时,可以用其分析DNA的种属来源;2个基因座对人和动物均有扩增产物,且片段长度相近,在进行个人识别时,应先作DNA种属来源检查。