EA-YPredictor:基于Y-STR数据的家系特异性单倍群归属判别分析软件

目的Y染色体为男性所特有,其遗传标记蕴含着丰富的生物地理信息,故可溯源家系,在嫌疑人排查和追踪中发挥作用。Y-STR突变率较高,而Y-SNP突变率极低,几乎不会发生回复突变,所以后代男性群体携带祖先特有的Y-SNP。本研究期望通过现在我国Y库建设中通用的17个Y-STR的单倍型数据预测Y-SNP单倍群细支。方法基于前期观察,选取千人基因组计划III期中的513例东亚人群(中国及周边区域)作为基础数据集,在Java平台和Microsoft Excel软件框架下,以遗传距离计算和Y染色体进化树构建手段相联合研发Y-STR数据的家系特异性单倍群归属判别分析软件:EA-YPredictor。结果本研究揭示了15个单倍群大支下的核心单倍型。通过随机选取70个公开数据库样本,EA-YPredictor软件预测准确性达到92.8%(95%置信区间:[84.1%,97.6%])。结论在Y-SNP复合扩增检测尚无定论的情况下,本软件可基于二代测序样本对Y-STR数据库样本进行单倍群细支的准确预测,能适用于辅助家系单倍群判断。随着测序技术的不断换代和优化,更多高通量的Y-STR和Y-SNP数据补充将会使本软件进一步优化。此外,本软件对于Y数据库中Y-SNP遗传标记的筛查建库有一定指向作用。     

Y染色体SNPs及其在法医学中的应用

Y-SNPs综合了Y染色体和SNPs的特点,具有男性特异性,突变率低,日益引起法医学工作者的关注。本文综合介绍了Y-SNPs的特性、单体群的命名规范及在法医学中的应用价值。     

Forensic application of Y chromosome SNPs in inconclusive cases

Biallelic markers, Single Nucleotide Polymorphisms (SNPs), are nowadays a powerful tool in the analysis of degraded samples. Namely, Y chromosome SNPs allow to determine the gender of the analyzed sample and to establish its haplogroup, making possible to attribute the ethnicity of male individuals. The aim of this study is to obtain Y-SNPs in forensic samples without STRs results, checking methodologies previously used.     

Y-SNPs analysis using two different approaches in a Northern Portugal male population sample

The non-recombining portion of the human Y (NRY) chromosome has various types of variation, including single nucleotide polymorphism (SNP). In spite of their low discrimination power, they provide a powerful and simple exclusion tool for forensic purposes. A special advantage of SNPs is that it can potentially detect smaller DNA fragments (analysis of degraded DNA).The aim of this work consisted in the analysis of a group of SNP polymorphisms (M2, M9, M35, M89, M45, M170, M172, M173, M207 and P25) in a Northern Portugal male population sample, which allows the determination of the most common European haplogroups, including the Northern Portugal ones.The method used for typing these polymorphisms was the real-time PCR with TaqMan probes on the ABI 7000 platform (Applied Biosystems).We had some difficulties in typing some of the markers using this approach. However, the preliminary results obtained for the defined haplogroups are in accordance with those described in close European populations. To confirm the typing and solve the doubts that emerged from the real-time approach, the samples were also typed using SNapShot.     

武汉汉族8个Y染色体双等位基因标记遗传多态性

目的筛选汉族群体中具有多态性的Y染色体双等位基因标记并研究其等位基因及单体群频率分布, 为法医学应用和群体进化研究提供基础数据。方法采用片段长度差异等位基因特异性PCR和PAGE技术对武汉地区160名男性汉族无关个体的8个Y染色体双等位基因标记(M9、M89、M111、M119、M122、M134、IMS-JST003305 和SRY+465)进行分型。结果 8个双等位基因标记在武汉汉族群体中均具有遗传多态性,其基因多样性(GD)范围为 0．0126-0．4830,共检出9种不同单体群(Hg1～9),其单体群多样性(HD)为0．7776。结论 8个Y染色体双等位基因标记组成的单体群在法医学应用和群体进化研究中具有一定的实用价值,可作为Y-STRs标记的有效补充。     

Multiplex PCR development of Y-chromosomal biallelic polymorphisms for forensic application

Single-nucleotide polymorphisms of Y chromosome (Y-SNPs) are a class of markers of interest in forensic investigations, because many of them show regional specificity, providing useful information about the geographic origin of a subject or evidence under investigation. A first multiplex with 7 SNPs (M35, M89, M9, M170, M172, M45, M173), which occur in the basal branches of the phylogenetic tree and are able to assign a subject to known most frequent European haplogroups, was designed. SNP genotyping was accomplished by hot-start PCR with primers amplifying fragments between 96 and 136 nucleotides, minisequencing, and capillary electrophoresis of extension products. Ninety seven subjects of known geographic provenance were studied, of which 68 from Europe. Of these, 57 had mutations found more frequently in European haplogroups and 11 more frequent in Asian populations. Subjects from non-European countries were also examined and had haplogroups common in their regions of provenance. Experiments with low molecular weight DNA gave positive amplification from 1 ng of DNA for all seven SNPs.     

孔姓人群Y染色体遗传多态性研究及其法医学意义

目的获取孔姓人群Y-SNP和Y-STR遗传标记的信息,探索姓氏与Y染色体的关联性及法医学意义。方法采用等级复合扩增和SNaPshot技术检测255例孔姓男性和330例随机无关男性样本的12个Y-SNPs位点信息;采用Y filer试剂盒检测孔姓人群的17个Y-STRs基因座;应用Arlequin 3.5.1.2、Network4.6.1.1进行统计分析。结果12个Y-SNPs位点构成13种单倍群分型,孔姓人群和无关人群中最高分布频率的单倍群均为O3a2c1a-M117(21.57%,14.85%)。孔姓人群17个Y-STRs基因座构成的196种单倍型,多态性为0.993 9,单倍型14-12-25-28-19-15-12-19-12-11-12-22-12-11-14-10-19出现15次。O3-M122单倍群的中介网络树及不配对差异分析显示孔姓人群有两个中心星型分布,核苷酸不配对曲线呈单峰泊松分布。结论联合Y-SNP和Y-STR遗传标记分析表明孔姓人群存在复杂的基因交流,有多个姓氏起源,且在历史上经历过一定的扩张或持续增长,结合孔姓家谱历史分析其人群结构的遗传差异在法医学方面有潜在的应用价值。     

Typing of mitochondrial DNA coding region SNPs of forensic and anthropological interest using SNaPshot minisequencing

The development of new methodologies for high-throughput SNP analysis is one of the most stimulating areas in genetic research. Here, we describe a rapid and robust assay to simultaneously genotype 17 mitochondrial DNA (mtDNA) coding region SNPs by minisequencing using SNaPshot. SNaPshot is a methodology based on a single base extension of an unlabeled oligonucleotide with labeled dideoxy terminators. The set of SNPs implemented in this multiplexed SNaPshot reaction allow us to allocate common mitochondrial West Eurasian haplotypes into their corresponding branch in the mtDNA skeleton, with special focus on those haplogroups lacking unambiguous diagnostic positions in the first and second hypervariable regions (HVS-I/II; by far, the most common segments analyzed by sequencing). Particularly interesting is the set of SNPs that subdivide haplogroup H; the most frequent haplogroup in Europe (40–50%) and one of the most poorly characterized phylogenetically in the HVS-I/II region. In addition, the polymorphic positions selected for this multiplex reaction increase considerably the discrimination power of current mitochondrial analysis in the forensic field and can also be used as a rapid screening tool prior to full sequencing analysis. The method has been validated in a sample of 266 individuals and shows high accuracy and robustness avoiding both the use of alternative time-consuming classical strategies (i.e. RFLP typing) and the need for high quantities of DNA template.     

Typing of mitochondrial DNA coding region SNPs of forensic and anthropological interest using SNaPshot minisequencing

The development of new methodologies for high-throughput SNP analysis is one of the most stimulating areas in genetic research. Here, we describe a rapid and robust assay to simultaneously genotype 17 mitochondrial DNA (mtDNA) coding region SNPs by minisequencing using SNaPshot. SNaPshot is a methodology based on a single base extension of an unlabeled oligonucleotide with labeled dideoxy terminators. The set of SNPs implemented in this multiplexed SNaPshot reaction allow us to allocate common mitochondrial West Eurasian haplotypes into their corresponding branch in the mtDNA skeleton, with special focus on those haplogroups lacking unambiguous diagnostic positions in the first and second hypervariable regions (HVS-I/II; by far, the most common segments analyzed by sequencing). Particularly interesting is the set of SNPs that subdivide haplogroup H; the most frequent haplogroup in Europe (40-50%) and one of the most poorly characterized phylogenetically in the HVS-I/II region. In addition, the polymorphic positions selected for this multiplex reaction increase considerably the discrimination power of current mitochondrial analysis in the forensic field and can also be used as a rapid screening tool prior to full sequencing analysis. The method has been validated in a sample of 266 individuals and shows high accuracy and robustness avoiding both the use of alternative time-consuming classical strategies (i.e. RFLP typing) and the need for high quantities of DNA template.     

Y chromosome SNP analysis in a Portuguese population sample using a multiplex PCR and minisequencing strategy

The study of single nucleotide polymorphisms (SNPs) located on the Y chromosome specific region Y-SNPs (92R7, M70, M22, Tat, P25, SRY10831, M173, M213 and M9) was used to characterize a population sample from Central Portugal, in order to investigate the frequency distribution of the male lineages and to compare the observed results with those obtained in other Portuguese regions.The genotyping strategy was according to the described by Brion et al. [M. Brion, et al., Int. J. Legal Med. 119 (2004) 10-15].In this population sample from Central Portugal a typical Western European haplogroup composition was found. The majority of samples (almost 70%) were assigned inside haplogroup R. As for other Iberian populations, the most frequent haplogroup was R1b-P25 (52.2%), followed by F(xK)-M213 (15.2%), E-B-SRY10831.1, R1(xR1a,b)-M173 and R1a-SRY10831.2 (each of them with a 8.7% frequency), K2-M70 (4.3%) and L-M22 (2.2%). When comparing our sample with other samples from Portugal, no significant differences were found.     

Y chromosome J2 subtyping in an Italian sample: Population and forensic implications

In the recent years the Y chromosome genealogy has been refined by a number of newly discovered SNPs. The non-random distribution of the Y chromosome lineages worldwide makes fundamental the dissection and characterisation of haplogroups associated with specific geographic areas. In Southern Europe the haplogroup J2, as defined by the M172 marker, can reach frequencies up to 35%, making the dissection of such lineage critical for population studies. Here we present a study on J2 chromosomes from the Italian peninsula. Populations and forensic implications are discussed. A total of 900 individuals were previously genotyped for a number of SNPs, including M172. More than 200 of these have been now genotyped for 7 SNPs within the J2 lineage using a multiplex SNaPshot approach. The different distribution of the various lineages in different geographic areas probably reflects different historical demographic events and points to differential Y chromosome haplotype distribution, with implication for forensic application of this genetic marker.     

Haplogroup prediction in the Ghanaian population using haplotype data of 27 Yfiler® Plus loci and TaqMan SNP genotyping

This study describes the use of the 27 loci Yfiler® Plus kit and TaqMan™ SNP genotyping to characterise and predict the haplogroups of Y chromosomes within the four major ethnic populations of Ghana. Haplogroups were assigned using the desktop NevGen software (https://www.nevgen.org/). The E1b1a and E1b1b haplogroups are the most common in the Ghanaian population and form 95% of the dataset. The Mole-Dagomba sub-population had 4. 8% assigned to the haplogroups G, H, R1b, R2 and T. The Ewe had two samples assigned to haplogroups C and D whilst the Akan had one sample each assigned to haplogroups B, J1 and J2. The NevGen predicted haplogroups were further screened with TaqMan™ genotyping for confirmation. In conclusion, ≈ 95% of the dataset was classified as M-E1b1a using NevGen combined with TaqMan™ SNP Genotyping for confirmation. The TaqMan™ also revealed 5% as J1 and other haplogroups, using an in-house control from the J1 haplogroup.     

云南白族群体Y-STR及Y-SNP关联性探讨

目的探讨Y-STR与Y-SNP单倍群间的关联性及其法医学应用价值。方法用Y-filer的17个Y-STR基因座及6个Y-SNPs（M122、M95、M9、M130、M119和M45）对云南白族146名无关男性个体样本进行检测。结果①17个Y-STR基因座构成的单倍型在146名男性个体中共检出114种单倍型,其中93种仅出现于一名个体中。②6个Y-SNPs在白族中的频率为4.1%～47.3%,其中O3-M122频率最高,占47.3%。③综合两类遗传标记结果,出现于2名或2名以上个体的21种Y-STR单倍型中,有5种其Y-SNP不同;分别只有一个Y-STR基因座分型不同的29对单倍型中,有8对其Y-SNP分别不同。Y-SNP单倍群间部分Y-STR基因座等位基因频率分布存在一定差异。结论 Y-STR单倍型相同或相近的个体间其Y-SNP分型可不相同,结合两者进行检测分析对于男性嫌疑人家系排查具有重要意义。     

Assessing the potential application of X-chromosomal haploblocks in population genetics and forensic studies

Haploblocks are segments of the genome with little recombination that may be of interest in forensic and population genetics. Criteria to select autosomal haploblocks have been previously described, leading to the identification of candidate regions that, a priori, met the conditions to be used as forensic genetic markers. Still, the potential of X-chromosomal haploblocks remains unexplored.The present work aimed to provide basis for designing strategies for selection of X-haploblocks defined by single nucleotide polymorphisms (SNPs) using next generation sequencing approach. The potential application in population genetics and forensic studies was addressed. One of the conditions considered in the haploblock selection was the simultaneous inclusion of short tandem repeats (STRs) currently used in forensic casework to allow the distinction between SNP-defined haplotypes and increase the resolution for fine-scale studies. Given the size of the X chromosome (∼150 Mbps), only four haploblocks could be selected in order to guarantee their independence.     

Development of multiplex PCRs for evolutionary and forensic applications of 37 human Y chromosome SNPs

This work describes an efficient and rapid test for typing 37 single nucleotide polymorphisms (SNPs) of the non-recombining region of Y chromosome (NRY) from a minimal amount of DNA using six PCR multiplexes. Markers were drawn following a hierarchical strategy based on the phylogenetic tree of Y chromosome proposed by the Y Chromosome Consortium [The Y Chromosome Consortium, A nomenclature system for the tree of human Y-chromosomal binary haplogroups, Genome Res. 12 (2002) 339-348]. Two multiplexes--arbitrarily named MY1 and MY2--were developed to explore the basal branches of the tree encompassing all the major clades A-R: MY1 for markers M35, M89, M172, M170, M9, M173, M45 and MY2 for markers M52, M216, M174, M181, M201, M91, M96, M214. Four multiplexes able of typing the more superficial branches typical of most frequent European haplogroups E3b, J2, R1 and I, were also developed and named MY-E3b (M78, M107, M224, M165, M148, M81), MY-J2 (M158, M68, M47, M102, M137, M67), MY-R1 (M17, M269, M18, P25, SRY10831.2) and MY-I (M72, M223, M26, M21, M161). SNP genotyping was carried out by hot-start PCR amplification with primers yielding fragments between 63 and 210 nucleotides, followed by minisequencing reaction based on dideoxy single-base extension and capillary electrophoresis of extension products. The sequential application of these multiplexes is a robust and effective resource for typing the most frequent European Y-SNP haplogroups, and appears to be suitable for forensic purposes and evolutionary studies.     

Analysis of 124 SNP loci included in HID Ampliseq identity panel in a small population of Rio de Janeiro,Brazil

Implementation of massively parallel sequencing platforms can bring a great contribution to Forensic Genetics field, with a great saving of time and costs, as well as allowing reliable results to be obtained from small or extremely degraded samples. The aim of this work was to analyze 124 SNP loci (90 autosomal and 34 Y-SNP) included in HID-Ion Ampliseq Identity Panel in a small sample from Rio de Janeiro state, Brazil. Samples from 12 non-related individuals were amplified with HID-Ion Ampliseq Identity Panel and sequenced on the Ion Torrent PGM platform (Thermo Fisher Scientific); genotypes were generated with HID SNP Genotyper plugin and forensic parameters were calculated with PowerStats v.12. All samples were successfully genotyped and were used to calculate allele frequencies, homozygosity, heterozygosity, random match probability (RMP) and exclusion power for all 90 autosomal SNP loci. Using the formula proposed by Budowle et al. (1996), only 4 of the 90 loci genotyped (4,4%) showed allele frequencies below the minimum required. It means that although a small set of individuals was used on this study, it may have shown a good perspective of Rio de Janeiro state allele frequencies. Among the 11 male samples analyzed, a prevalence of the haplogroup R1b of Y chromosome was observed, followed by the haplogroups E, Q and J. Such distribution reflects the results demonstrated in other studies for the population of Rio de Janeiro. All results together demonstrate the usefulness and applicability of SNP analysis on Ion Torrent PGM.     

A new strategy for the discrimination of mitochondrial DNA haplogroups in Han population

Mitochondrial DNA (mtDNA) haplogroup discrimination is interesting not only for phylogenetic and clinical but also for forensic studies. We discriminated the mtDNA haplogroups of 570 healthy unrelated Han people from Zhejiang Province, Southeast China, by comprehensive analysis mutations of the hypervariable segments-I sequence and diagnostic polymorphisms in mtDNA coding region using real-time polymerase chain reaction (RT-PCR), which was compared with the widely used PCR and restriction fragment length polymorphism (PCR-RFLP) method. The results showed that in superhaplogroup M, haplogroup D was the most common haplotype within this assay to 24.6%, and in the other superhaplotype N, haplogroup B and F were the most common groups. Samples re-identified by PCR-RFLP showed the consistent results that were got with RT-PCR. In conclusion, the RT-PCR strategy appears to be an accurate, reproducible, and sensitive technique for the discrimination of mtDNA haplogroups, especially for mass screenings quickly and economically.     

Make it "SNPPY" - Updates to SRM 2391d: PCR-Based DNA Profiling Standard

Standard Reference Material (SRM) 2391d: PCR-Based DNA Profiling Standard was released to the forensic community in 2019. Next Generation Sequencing (NGS) was used as the primary method of certification, where certified values were assigned when a high coverage sequence string was available for a marker. Using NGS to assign values has allowed for additional marker sets beyond short tandem repeat (STR) loci, including single nucleotide polymorphisms (SNPs) and mitochondrial DNA (mtDNA) whole genome sequences, to be included in the Certificate of Analysis (COA). Since the 2019 release, several commercial NGS panels have become available including the Verogen ForenSeq mtDNA Control Region, mtDNA Whole Genome, MainstAY, and Kintelligence Kits. In addition, three community Ion AmpliSeq panels from Thermo Fisher (MH-74 Plex, VISAGE, and Y-SNP) are now available. While the mtDNA whole genome sequence for the components are already included and no new STR markers are introduced by MainstAY, the other recently released panels allow for the inclusion of > 11,000 additional SNPs (e.g., identity, ancestry, phenotype, kinship, and X- and Y-SNPs) and 74 microhaplotypes to the COA for SRM 2391d in an update completed by fall of 2022.     

The genetic male legacy from El Salvador

Allele frequencies and haplotype and haplogroup analysis have been performed for 16 Y-chromosome binary markers and 8 Y-chromosome STRs (DYS19, DYS385I and II, DYS389I and II, DYS390, DYS391, DYS392, DYS393). Data was obtained from a general sample of 93 unrelated individuals living in metropolitan areas from El Salvador, and 67 individuals from different historical ethnic groups, Conchagua, San Alejo, Panchimalco, Izalco and finally Nueva Concepción with white people. Levels of admixture among metropolitan and rural areas were evaluated and population substructure measured. A total of 13 haplogroups and 136 different haplotypes were found. The most frequent haplogroup in the general metropolitan population was the European R1b, while in the Indigenous samples considered as a whole the most frequent was the Amerindian haplogroup Q3.     

Y-chromosome markers distribution in Northern Africa: High-resolution SNP and STR analysis in Tunisia and Morocco populations

At the beginning of 2006 more than 301,000 immigrants resident in Italy resulted to come from Tunisia and Morocco, 66% of which are male subjects; in addition, it is estimated that some other thousand are clandestine. Our data show that there is an increasing involvement of Tunisian and Moroccan individuals in paternity testing and in individual identification cases. For these reasons, the aim of this work was to enrich forensic Y-chromosome databases with Northern Africa data to better know markers frequency and their distribution across these populations (in YHRD there are 246 Tunisian samples and 0 Moroccans, access date to www.yhrd.org: August 2007). 103 Tunisian and Moroccan healthy male donors were typed by 17 microsatellites extended haplotype and 41 Y-SNPs. A high-resolution level database was created, including both haplotype and haplogroup for each sample. This study confirmed that precious informations might come both from Y-SNPs haplogroup distribution besides Y-STRs data.