辽宁汉族人群11个Y—STR基因座遗传多态性

Y染色体STR扩增片段短、多态信息含量高，突变率与常染色体STR相当，我们对辽宁汉族男性群体的Y染色体11个STR基因座的等位基因频率和单倍型频率进行调查，为相关工作提供基础数据。     

苏北地区汉族人群19个Y—STR基因座的遗传多态性

Y染色体短串联重复序列（Y—STR）作为常用的Y染色体特异遗传标记，在法医学个体识别、亲子鉴定、混合斑中男性成分检测、追溯父系迁移历史f1J等方面都具有独特的应用价值，是常染色体及mtDNA的重要补充。本研究调查了苏北地区642名汉族无关男性个体的19个Y—STR基因座的遗传多态性，以期为该群体的DNA检验鉴定提供基础数据。     

中国朝鲜族2个Y-STR基因座遗传多态性

Y染色体为男性特有,位于Y染色体上的STR基因座具有非重组父系遗传特性,故广泛应用于父系关系鉴定和群体父系遗传学研究[1-2]。本文调查中国朝鲜族男性个体DYS447和DYs448基因座单倍型遗传多态性,为相关数据库补充基础数据。     

EX16+10Y试剂盒检测新疆维吾尔族人群的效能

目的检验EX16+10Y试剂盒在新疆维吾尔族人群中的法医学检测效能。方法采集4 620个新疆地区维吾尔族男性个体血样,用EX16+10Y试剂盒进行扩增,用3130xl基因分析仪对扩增产物进行分型。结果获得4 620个新疆维吾尔族男性个体的15个常染色体STR基因座和10个Y染色体STR基因座的完整分型图谱。15个常染色体STR基因座分布均符合Hardy-Weinberg平衡,STR基因座的杂合度为0.637~0.838,多态信息含量为0.580~0.860,个体识别率为0.811~0.978。10个Y染色体STR基因座有766种单倍型。结论 EX16+10Y试剂盒检测结果准确可靠,可用于实际工作中同时完成个体识别和男性家系排查。     

荧光复合扩增4个Y染色体STR的单倍型及其法医学应用

目的建立一套Y染色体STR的双色荧光复合扩增系统,调查4个Y-STR基因座单倍型分布情况及其在混合斑物证检验中的法医学应用前景。方法荧光标记引物复合扩增Y-GATA-A10、DYS531、DYS557和DYS448四个Y染色体特异性STR基因座,并用ABⅠ310遗传分析仪对扩增产物进行检测、分型。结果在成都汉族120名无关男性个体中,四个基因座分别检出5、5、8、7个等位基因,共检出78种单倍型,单倍型基因多样性为0.9881。对3例本教研室不能用常规常染色体STR对男性成份作出同一认定的混合斑检材,该系统成功的作出了与嫌疑人血液Y-STR基因型一致的鉴定结论。结论建立的Y-STR荧光标记复合扩增系统具有很高的识别能力,对建立Y染色体STR数据库,研究群体遗传学和进行法医学混合斑物证鉴定有重要意义。     

Y—STR基因座的特殊分型现象

Y染色体为男性所特有，在减数分裂中呈连锁遗传，在法医学中具有常染色体基因座不可比拟的独特作用。自从1997年Kayser首次报道DYS19基因座以来．越来越多的Y—STR基因座被发现与应用。     

STR分型技术在一宗寻亲案中嵌合体法医学分析中的应用

嵌合体是包含有两个或以上不同细胞系的生物个体。本文运用STR分型技术对一宗寻亲案中的男性嵌合体的类型、形成机制及其不同组织样本中的嵌合现象进行探究。结果表明，该嵌合体属于四配子异源嵌合体，为卵母细胞孤雌分裂产生的两个相同配子双受精后发生融合所形成。由于两个细胞系分布情况不同，嵌合体的不同样本检出了不同的STR分型，最后通过精液检出的男性分型成功比中了其失踪多年的儿子。     

潍坊地区汉族人群25个Y-STR遗传多态性

<正>Y染色体具有男性特有、父系遗传及单倍型遗传的特征,在法医学检验中作用独特。本文调查了潍坊汉族男性Y染色体上的25个STR基因座的遗传多态性,以期为法医学应用及相关研究与实践提供基础数据。1材料与方法1.1样本及DNA提取1 000名健康无父系亲缘关系的汉族男性个体FTA卡血样采集于潍坊地区,采用Chelex-100法提     

新疆维吾尔族群体22个Y-STR基因座的多态性分析

正短串联重复序列(STR)广泛存在于人类基因组中,其长度多态性使得其在法医物证学中有着十分重要的应用,无论在常染色体还是性染色体上,均可选取适当的位点进行扩增分型以达到个体识别和亲权鉴定的目的。与常染色体的遗传方式不同,男性特有的Y染色体呈父系遗传,若无突变发生,同一父系的男性个体均具有相同的Y-STR单倍型,这一特点使     

天津汉族人群12个Y-STR基因座的遗传多态性

目的　建立天津汉族 2 10名无关男性人群 12个Y STR基因座单倍型分布基础遗传数据库。探讨其法医学应用价值。方法　应用PowerPlex YSystem (PromegeCorporation ,USA)荧光标记复合扩增系统、ABI 310 /377型基因分析仪进行检测 ,统计各基因座的单倍体基因频率 ,计算其GD值即基因差异性 (GeneDiversi ty)。结果　 12个Y STR基因座中共检出 2 0 8种单倍型。其中 ,2 0 6种单倍型均出现 1次 ,2种单倍型出现 2次。GD值在 0 32 5 9～ 0 8810之间 ,累计GD值 (TGD)为 0 9999988。另对 2 8个父性家系调查显示 :同一家系(2～ 7名男性 ) 12个Y STR基因座单倍型一致。结论　天津汉族 12个Y STR基因座多态性分布良好 ,父系遗传稳定 ,适用于法庭科学中的个体识别和亲权鉴定     

Parentage of Hydatidiform Moles

We were presented with the STR (short tandem repeat) profiles from two separate paternity trios. Each trio consisted of a mother, an alleged father, and products of conception (POC) that contained a hydatidiform mole but no visible fetus. In both cases , antecedent pregnancies had followed alleged sexual assaults. Mole classification and pathogenesis are described in order to explain the analyses and statistical reasoning used in each case. One mole exhibited several loci with two different paternal alleles, indicating it was a dispermic (heterozygous) mole. Maternal decidua contaminated the POC, preventing the identification of paternal obligate alleles (POAs) at some loci. The other mole exhibited only one paternal allele/locus at all loci and no maternal alleles, indicating it was a diandric and diploid (homozygous) mole. In each case, traditional calculations were used to determine paternity indices (PIs) at loci that exhibited one paternal allele/locus. PIs at mole loci with two different paternal alleles/locus were calculated from formulas first used for child chimeras that are always dispermic. Combined paternity indices in both mole cases strongly supported the paternity of each suspect.     

A STR mutation in a heteropaternal twin case.

A heteropaternal male twin case with two men being alleged fathers was investigated as requested by the Court. Up to 37 PCR-based polymorphic DNA systems were studied in this case which was complicated by a paternal ACTBP2 mutation detected in one twin. This is the first report on a STR mutation in a double paternity case where both biological fathers were indisputably identified. The STR systems enable the resolution of these complex genetic relationships even in a case where a mutation in one STR locus was encountered.     

A molecular classification of moles and its use in filiation tests

Pregnancies, including ones that follow sexual assaults, occasionally produce hydatidiform moles. The alleged fathers (AFs) of moles have been tested for paternity by identifying the mole's locus phenotype—the one or two visible paternal obligate alleles (POAs) per locus. The probability that the mole inherited the POAs from the AF was divided by the probability that the mole inherited the POAs from a random man. This likelihood ratio (LR) would increase if the mole's specific genotype was known. Moles are generated in five different ways that produce five distinct genotypes. Examining a mole's multilocus STR profile reveals a mole's pathogenesis, determines locus genotypes, and increases paternity LRs.     

Two loci ‘exclusion’ of true paternity is due to genetic disorder in a child

We describe a paternity case with three genetic incompatibilities between a three-year-old boy and his putative father.STR analysis of 2 out of 25 markers revealed the absence of paternal alleles and presence of two maternal alleles at D2S441 and D2S1338 loci in the child. The rest 23 STR markers served to confirm paternity. In addition, we analyzed Y-STRs and determined the same haplotype in the child and his putative father.With massive parallel sequencing on HID Ion GeneStudio S5 System using Precision ID GlobalFiler NGS STR Panel v2 (Applied Biosystems) we confirmed the presence of two alleles of maternal origin at D2S441, D2S1338 loci and identified two maternal alleles at additional locus D2S1776 located on chromosome 2 in the child.Finally, we confirm paternity. Three loci ‘exclusion’ was due to maternal uniparental disomy of chromosome 2 in the child.     

What is she doing here? Klinefelter syndrome in forensic casework

In this case report, we describe a sexual assault incident in which the male victim’s seminal fluid contained no sperm cells, as indicated by sperm cell staining and microscopic screening, and DNA profiling results from the non-sperm cell fraction showed a major/minor DNA mixture that could be interpreted as female and male. DNA profiling of a sample from a disposable drinking cup used by the victim at the crime scene provided a single source profile, and showed a 2:1 imbalance between the heights of the X and Y chromosomes, respectively. The victim’s DNA reference sample showed a similar imbalance of the X and Y chromosomes. These observations suggested that the victim might suffer from Klinefelter syndrome, a genetic disorder related to the sex chromosomes.Here, we describe the first reported use of the QIAGEN Investigator® Argus X-12 kit for characterization of X-chromosomal STR loci to potentially identify a case of Klinefelter syndrome. This commercially available kit is primarily used in forensic laboratories to investigate kinship relations and for paternity testing in alleged father/daughter cases. Results of the X chromosome DNA profiling from the victim’s disposable drinking cup and reference samples revealed two alleles at various X-chromosomal STR loci. Moreover, this kit can also amplify a Y chromosome specific sequence (AMEL-Y), and the results indicated that this sample actually originated from a male. Evidence of two X chromosomes in the victim's DNA suggested that he was likely to have Klinefelter syndrome. In this case report, we propose the use of the QIAGEN Investigator® Argus X-12 kit as a practical forensic tool for the detection of potential genetic syndromes related to the sex chromosomes, which can affect test results and, at times, make them difficult to interpret. We also aim to increase awareness within the forensic science community regarding the existence of genetic anomalies, which should be considered when analyzing DNA profiles.     

Identification of gestational trophoblastic disease in a sexual assault case

In this study, gestational trophoblastic disease (GTD) was observed by short tandem repeat (STR) typing from the aborted tissues in a sexual assault case. By histological screening, the fetal tissue could not be distinguished from the maternal tissue in this case. Therefore, five specimens were collected randomly from the aborted tissues for DNA analysis. STR typing was performed by the commercial ABI Identifiler kit. The results showed that three specimens were of the maternal origin, one was a mixture of the mother and male fetus, and the other one was of male fetal origin with partial triploid. Three alleles were identified in each locus of D8S1179, D7S820 and VWA for the fetal specimen. For these three alleles, one matched the maternal origin and the others matched the putative paternal origin (suspect). Analysis of the Y-STR by using the commercial ABI Y-Filer kit, the fetal types matched the types of the suspect. We reported the case of partial mole on forensic evidence and gave the valuable information from its identification.     

应用多种STR技术对基因嵌合体进行亲权鉴定分析

目的 查找嵌合基因的来源并进行父母和孩子的亲权鉴定.方法 采用Chelex-100法抽提基因组DNA,用复合扩增和荧光检测技术对STR、X-STR和Y-STR基因座进行分型.结果 父亲为XX,XY基因嵌合体,其能够提供给孩子必须的遗传基因.结论 父亲为被检孩子的生物学父亲.     

Detection of genotype recycling fraud in U.S. immigrants

Abstract: Relationship testing laboratories provide genetic evidence to support or refute claims of kinship between U.S. citizen petitioners and potential immigrant beneficiaries. One female beneficiary presented a male amelogenin type and alleles at 15 autosomal loci that were identical to an alleged brother’s. Laboratory records showed that her alleged father had petitioned to have 15 children emigrate from Ghana. The petitioner’s 15 paternity indices exceeded 10⁵, but the children shared only four short tandem repeat (STR) profiles, suggesting fraudulent reuse of genotypes in this alleged pedigree (AP). To determine the extent of this “genotype recycling,” I examined the laboratory’s 555 APs from Ghana and 532 control APs from Nigeria. Seventeen Ghanaian APs (3.1%) but no Nigerian APs showed genotype recycling. Of 90 tested people in the 17 APs, 56 shared identical STR profiles with others in their AP. Of these 56 people, 10 were petitioners with unexpectedly high parentage indices. Seven of 56 had amelogenin types that disagreed with their declared genders. Database searches for identical multilocus genotypes in allegedly different people would best detect this fraud.     

The extent of STR chimerism in different biological samples following bone marrow transplantation: A case report

Biological samples recovered from recipients of allogeneic haematopoietic stem cell transplant (HSCT) contain genetic material from both donor and him/herself. This chimeric condition can greatly complicate analysis of a DNA evidence and undermine its power of discrimination, as the specimens could be mistakenly identified as a mixed sample when in fact it originated from a single person. Profiling reference samples could help clarify the profile anomalies, however, the degree of mixture between host’s and donor’s genetic materials has been reported to vary depending on the tissue from which DNA were obtained. As a result, knowledge to select appropriate sources of reference samples that would most likely reveal the person’s pre- and post-transplant alleles becomes necessary to minimise any possible misunderstanding during the subsequent DNA profile interpretation and comparison. This work investigated the extent of chimerism present in different types of biological samples collected from an individual who had undergone a bone marrow transplant as a child (post-transplant interval, PTI >28 years). DNA profiles from buccal cells, saliva, hair roots, and fingernail clippings were generated using AmpFℓSTR™ Identifiler™ Plus/Direct PCR Amplification Kit. The donor’s STR profile was used to identify donor- and host-specific alleles (DSA and HSA, respectively), and relative donor chimerism (%Ch) of each marker was calculated. Results showed that the saliva sample contained the highest level of chimerism, with complete profile of donor being detected and the mean %Ch was 34.0 ± 4.5. Four out of eight DSA dropped out from the buccal cell profile, and the mean %Ch was 24.2 ± 1.7. Hair roots and fingernail clippings yielded single source profiles and only host’s original alleles were present. Except for the fingernail results, these observations agreed with many of the previous studies, which further demonstrated the need for raising awareness among forensic genetic laboratories regarding the type of reference samples that should be collected in future cases.     

Assessment of the Yfiler® Plus PCR amplification kit for the detection of male DNA in semen-negative sexual assault cases

The ability to detect male epithelial cells deposited during digital penetration or penile penetration without ejaculation is limited by the sensitivity of the Y-STR profiling kit. In this study, the relative profiling success of the Thermofisher Yfiler® Plus kit was compared to its predecessor, AmpFlSTR Yfiler®, for 104 semen-negative sexual assault samples from casework at Forensic Science SA, Adelaide, South Australia. Yfiler Plus generated allele information in 25% more samples than Yfiler and gave a higher recovery of informative alleles in all but two samples where detectable male DNA was present. Where a profile was obtained in both kits, 92% of samples gave a higher percentage of informative loci with Yfiler Plus compared to Yfiler. Yfiler Plus also resolved DNA mixtures in 15 samples as compared to 1 sample with Yfiler. Detection of male DNA with the Quantifiler™ Trio DNA Quantification kit was shown to correlate with a successful profiling outcome with Yfiler Plus. The success of profiling with Yfiler Plus was independent of the time elapsed between the alleged offence and the sample being collected, the type of sexual penetration which occurred, and the anatomical origin of the sample.