DNA的apoB位点扩增片段长度多态性的检测及其在法医学中的应用

用PCR方法对100例无关个体血样的apoB位点扩增片段进行研究,已发现有11个等位基因,片段长度分布于600～1100bp之间,基因频率为0.005～0.525,杂合度为70％。家系分析及对人体血液、血斑、精液、精斑、混合斑、带毛囊毛发及其它各种有核细胞组织的研究表明,该技术在个人识别及亲子鉴定上均能发挥重要作用。     

云南白族人群DlS80位点扩增片段长度多态性研究

本研究采用扩增片段长度多态性(Amp-FLP)分析技术,对116名云南白族人DIS80位点进行检测.共检出19个等位基因,52种基因型.扩增片段大小分布于340～780bp之间,基因频率分布为0.0043～0.2424,杂合度为85.34%,个人识别率(DP)为0.9606.     

pMCT118位点扩增片段长度多态性及其应用

本文报道了对98例中国人 pMCT118位点扩增片段长度多态性的等位基因频率调查及有关法医生物物证检验问题的研究。用多聚酶链反应、小型聚丙烯酰胺凝胶电泳和银染方法,在12h 内检测低至1ngDNA 的 pMCT118位点扩增片段长度多态性。已发现22个等位基因,大小分布在340～780bp 之间,基因频率为0.005～0.3,杂合度为79%。对6个家系22名相关个体的分析符合孟德尔定律。探讨了微量检材样品制备和对混合斑、单根毛囊、唾液等生物检材的法医应用。对20个实际案例进行了检验。     

p33.4位点扩增片段长度多态性及其法医学应用的研究

以聚合酶链反应（PCR）、聚丙烯酰胺凝胶垂直电泳和银染法对中国100名无关个体小卫星区域p33．4位点的扩增片段长度多态性（Amp－FLPs）进行了研究，检出了8个等位基因。通过BIOTRAC系统进行数据处理．各等位基因重复单位的数目分别为7、10到15，其中在13～14之间发现一差值不足一个重复单位长度的罕见等位基因。片段长度分布于603～1115bP之间，基因频率分布于0.5～33．5％间，杂合度为64％，DP值为84．5％。对5个家庭25名相关个体进行分析，符合孟德尔遗传定律；对同一个体不同组织的DNA进行P33.4位点的分型研究表明，该技术适宜于法医物证检验。此外，本研究以Chelex处理不同检材制备DNA模板用于扩增，率先建立了比常规方法更快、更简便、更为实用的检验方法。     

pYNZ22位点扩增片段长度多态性法医应用的研究

对120名中国人进行pYNZ22位点扩增、银染检测，已找到11个等位基因，频率分布于0.4～30.4％，片段长170bp～870bp，相邻等位基因长度相差70bp，杂合度为73％，DP值为0．938。分析了五个家系均符合孟德尔定律。同一个体的血液、血斑、精液、混合斑中分离出的精子、毛囊、唾液及其它有核细胞组织的DNA多次进行pYNZ22位点扩增，得到一致的结果。灵敏度达到0．5ng核DNA。     

云南白族人群DIS80位点扩增片段长度多态性研究

本研究采用扩增片段长度多太性(Amp—FLP)分析技术，对116名云南白族人DIS80位点进行检测。共检出19个等位基因，52种基因型。扩增片段大小分布于340～780bp之间，基因频率分布为0．0043～0．2424，杂合度为85.34%，个人识别半(DP)为0．9606。     

西安汉人D1S80位点基因频率调查

利用PCR技术、小型聚丙烯酰胶凝胶电泳及银染法，检测D1S80位点的VNTR扩增片段长度多态性（Amp－FLP）。在175名无关的西安地区汉族人群中发现了22个等位基因，片段大小分布于320～750bp之间，频率分布为0．0057～03314，杂合度为82．3％，个人识别率（DP）为0.9588，非父排除率（EPP）为0．6704。对7个家系23名相关个体分析，证实DIS80位点的遗传符合孟德尔方式。已发现的64种基因型分布符合Hardg－Weinberg定律。     

短串联重复位点ACTBP2(SE33)的扩增片段长度多态性研究

应用变性聚丙烯酸胺凝胶电泳（dn－PAGE）结合银染色技术对短串联重复（STR）位点ACTBP2（SE33）的扩增片段长度多态性（Amp－FLPs）进行了研究。在210名无关中国个体中观察到了25个等位基因，等位基因频率分布在0．007～0．093之间。基因型的分布符合Hardy－Weinberg定律，个体识别能力（DP）值为0．99，杂合度（H）为98．7％。七个家系分析的结果表明，该位点的遗传符合孟德尔遗传法则，未观察到变异。对几种常见的法医物证检材的分析表明，该分型系统对DNA降解放为严重的检村适用性强，而且灵敏度高（0．5ng），适合于法医学实际应用。     

成都地区汉族人群D2S441位点的遗传多态性研究

为研究 STR位点 D2S441的遗传多态性,为法医学应用提供基础数据,应用 PCR及 PAG电泳技术对 260名成都地区汉族无关个体进行了调查,共检出 9个等位基因及 26种基因型,首次获得汉族群体频率分布 ,其等位基因片段大小范围为 131～ 155bp。该位点基因型频率分布符合 Hardy－ Weinberg平衡。家系调查证实了等位基因的传递遵循孟德尔遗传规律。其个人识别能力（ Dp）、杂合度（ H）、多态性信息含量（ PIC）和非父排除率（ PE）分别为 0.9084、 0.7885、 0.7390和 0.5778,表明该位点在法医学个人识别及亲子鉴定中具有较高的实用价值。     

ABO位点限制性扩增片段长度多态性的研究

建立了PCR扩增、限制性酶切、8％（T）、5％（C）聚丙烯酸胺凝胶垂直电泳和银染检测ABO位点的限制性片段长度多态性的方法体系。应用Amp-RFLP技术对185名中国人（哈尔滨）ABO位点的基因频率和基因型分布进行了调查和统计分析。ABO位点特异片段长度为140～200bp，基因频率为0．2000～0．5568。6种基因型频率为0．973～0．3135，杂合度0．5838，Dp值0．7146。经H－W平衡吻合度检测，完全符合群体遗传多态分布。通过对11个家庭33名相关个体的分析，证明完全符合孟德尔遗传定律。ABO基因型检验适用于法庭科学的个体识别和亲权鉴定。     

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.     

The analysis of three short tandem repeat (STR) loci in the Slovene population by multiplex PCR

Allele frequencies for three tetrameric short tandem repeat (STR) loci D3S1358, HUMVWA, and HUMFGA were determined in a Slovene Caucasian population sample. DNA samples from a total of 221 Slovenes were amplified by multiplex PCR using the commercial kit AmpFISTR Blue (Perkin-Elmer). Separation and detection of the amplified STR fragments were carried out using a 377 automated genetic analyzer (Applied Biosystem Division/Perkin Elmer). Seven alleles at the D3S1358 locus, 8 alleles at the HUMVWA31A locus, and 13 alleles at the HUMFGA locus were observed. A deviation from Hardy-Weinberg equilibrium was observed, only at the HUMVWA31A locus (p = 0.045, exact test). The departure at this locus was not significant after Bonferroni correction. There were no detectable departures between pairwise comparisons of the loci. The combined power of discrimination for all three loci is 0.9998, and the power of exclusion is 0.9526. The observed allele frequencies for the loci D3S1358, HUMVWA31A, and HUMFGA are similar to those in European and U.S. Caucasian populations.     

STR HUMARA locus gene and genotype frequencies in Han and Bei populations in China.

For the purpose of the population genetics study of the HUMARA locus, the allele, and genotype frequencies were determined in two Chinese population samples (Han-101, Bei-113) using PCR, PAGE, and silver staining. Fourteen alleles were found. The size of amplified fragments were 258 bp-315 bp. The observed heterozygosities were 0.83 in the Han population and 0.73 in the Bei population respectively. The expected heterozygosities were 0.91 in the Han population and 0.97 in the Bei population respectively. Both populations meet Hardy-Weinberg expectation, Han population x2 = 17.7206, df = 11, p > 0.05; Bei population x2 = 7.4268, df = 10, p > 0.05. The discrimination power were 0.95 in females and 0.89 in males in the Han population, 0.94 in females and 0.88 in males in the Bei population. Thus, the allelic frequency data can be used in the personal identification and parentage testing in the forensic science practice. The PCR test established in this study is robust and reproducible.     

Identification of a novel polymorphism in the X-chromosome region homologous to the DYS456 locus

During an extensive multipopulation study with Y-short tandem repeat (STR) loci, amplified using the AmpFlSTR Yfiler PCR amplification kit, amplification of a 71 bp fragment was observed in 2.32% of the male samples analyzed (N = 3141). By direct sequencing of this fragment, it was determined that the primer binding sequences were identical to those of the DYS456 locus. A T to G single-nucleotide polymorphism (SNP) enabled amplification of the 71 bp fragment. The SNP is located within an X-Y homologous region at Xq21.31 and was observed with the highest frequency within the African American and Sub-Saharan African populations in our study. Presence of SNP on the X chromosome did not interfere with the reliability of typing the DYS456 locus and the other Y-STR loci typeable using the AmpFlSTR Yfiler PCR amplification kit. Full profiles in a mixture of male:female at 1:4000 were obtained using the current configuration of the AmpFlSTR Yfiler kit even in the presence of female DNA containing the G variant.     

A Y‐Chromosomal Haplotype with Two Short Tandem Repeat Mutations*

Abstract:  The male‐specific Y‐chromosomal short tandem repeat (STR) is a useful tool in forensic casework. The Y haplotype comprised of 16 loci, which is amplified simultaneously by AmpFlSTR^® Yfiler^TM PCR kit and provides strong exculpatory evidence in individual identification. We reported a rare Y‐STR profile with a null allele at the DYS448 locus and an off‐ladder allele at the DYS456 locus, when genotyping material from a vaginal swab in an alleged rape case. Sequence analysis revealed that the DYS448 null allele was a true type of null allele because of a total deletion of 11 upstream repeats and 9 bp of the N₄₂ region, and there were numerous primer binding site mutations as well. The amplicon of the DYS456 locus was a small 92‐bp fragment that was off‐ladder, and sequencing analysis showed that there were only 10 repeats (AGAT)₁₀. This Y chromosome haplotype that was comprised of two variations provided helpful evidence for personal identification.