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Large-scale genomic projects and ancient DNA innovations have ushered in a new paradigm for exploring human evolutionary history. However, the genetic legacy of spatiotemporally diverse ancient Eurasians within Chinese paternal lineages remains unresolved. Here, we report an integrated Y-chromosome genomic database encompassing 15,563 individuals from both modern and ancient Eurasians, including 919 newly reported individuals, to investigate the Chinese paternal genomic diversity. The high-resolution, time-stamped phylogeny reveals multiple diversification events and extensive expansions in the early and middle Neolithic. We identify four major ancient population movements, each associated with technological innovations that have shaped the Chinese paternal landscape. First, the expansion of early East Asians and millet farmers from the Yellow River Basin predominantly carrying O2/D subclades significantly influenced the formation of the Sino-Tibetan people and facilitated the permanent settlement of the Tibetan Plateau. Second, the dispersal of rice farmers from the Yangtze River Valley carrying O1 and certain O2 sublineages reshapes the genetic makeup of southern Han Chinese, as well as the Tai-Kadai, Austronesian, Hmong-Mien, and Austroasiatic people. Third, the Neolithic Siberian Q/C paternal lineages originated and proliferated among hunter-gatherers on the Mongolian Plateau and the Amur River Basin, leaving a significant imprint on the gene pools of northern China. Fourth, the J/G/R paternal lineages derived from western Eurasia, which were initially spread by Yamnaya-related steppe pastoralists, maintain their presence primarily in northwestern China. Overall, our research provides comprehensive genetic evidence elucidating the significant impact of interactions with culturally distinct ancient Eurasians on the patterns of paternal diversity in modern Chinese populations.
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Povo Asiático , Cromossomos Humanos Y , Migração Humana , Humanos , China , Povo Asiático/genética , Masculino , Cromossomos Humanos Y/genética , DNA Antigo/análise , Herança Paterna , Filogenia , População do Leste AsiáticoRESUMO
BACKGROUND: The underrepresentation of Hmong-Mien (HM) people in Asian genomic studies has hindered our comprehensive understanding of the full landscape of their evolutionary history and complex trait architecture. South China is a multi-ethnic region and indigenously settled by ethnolinguistically diverse HM, Austroasiatic (AA), Tai-Kadai (TK), Austronesian (AN), and Sino-Tibetan (ST) people, which is regarded as East Asia's initial cradle of biodiversity. However, previous fragmented genetic studies have only presented a fraction of the landscape of genetic diversity in this region, especially the lack of haplotype-based genomic resources. The deep characterization of demographic history and natural-selection-relevant genetic architecture of HM people was necessary. RESULTS: We reported one HM-specific genomic resource and comprehensively explored the fine-scale genetic structure and adaptative features inferred from the genome-wide SNP data of 440 HM individuals from 33 ethnolinguistic populations, including previously unreported She. We identified solid genetic differentiation between HM people and Han Chinese at 7.64â15.86 years ago (kya) and split events between southern Chinese inland (Miao/Yao) and coastal (She) HM people in the middle Bronze Age period and the latter obtained more gene flow from Ancient Northern East Asians. Multiple admixture models further confirmed that extensive gene flow from surrounding ST, TK, and AN people entangled in forming the gene pool of Chinese coastal HM people. Genetic findings of isolated shared unique ancestral components based on the sharing alleles and haplotypes deconstructed that HM people from the Yungui Plateau carried the breadth of previously unknown genomic diversity. We identified a direct and recent genetic connection between Chinese inland and Southeast Asian HM people as they shared the most extended identity-by-descent fragments, supporting the long-distance migration hypothesis. Uniparental phylogenetic topology and network-based phylogenetic relationship reconstruction found ancient uniparental founding lineages in southwestern HM people. Finally, the population-specific biological adaptation study identified the shared and differentiated natural selection signatures among inland and coastal HM people associated with physical features and immune functions. The allele frequency spectrum of cancer susceptibility alleles and pharmacogenomic genes showed significant differences between HM and northern Chinese people. CONCLUSIONS: Our extensive genetic evidence combined with the historical documents supported the view that ancient HM people originated from the Yungui regions associated with ancient "Three-Miao tribes" descended from the ancient Daxi-Qujialing-Shijiahe people. Then, some have recently migrated rapidly to Southeast Asia, and some have migrated eastward and mixed respectively with Southeast Asian indigenes, Liangzhu-related coastal ancient populations, and incoming southward ST people. Generally, complex population migration, admixture, and adaptation history contributed to the complicated patterns of population structure of geographically diverse HM people.
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População do Leste Asiático , Genética Populacional , Humanos , China , Genômica , Haplótipos , FilogeniaRESUMO
BACKGROUND: The underrepresentation of human genomic resources from Southern Chinese populations limited their health equality in the precision medicine era and complete understanding of their genetic formation, admixture, and adaptive features. Besides, linguistical and genetic evidence supported the controversial hypothesis of their origin processes. One hotspot case was from the Chinese Guangxi Pinghua Han people (GPH), whose language was significantly similar to Southern Chinese dialects but whose uniparental gene pool was phylogenetically associated with the indigenous Tai-Kadai (TK) people. Here, we analyzed genome-wide SNP data in 619 people from four language families and 56 geographically different populations, in which 261 people from 21 geographically distinct populations were first reported here. RESULTS: We identified significant population stratification among ethnolinguistically diverse Guangxi populations, suggesting their differentiated genetic origin and admixture processes. GPH shared more alleles related to Zhuang than Southern Han Chinese but received more northern ancestry relative to Zhuang. Admixture models and estimates of genetic distances showed that GPH had a close genetic relationship with geographically close TK compared to Northern Han Chinese, supporting their admixture origin hypothesis. Further admixture time and demographic history reconstruction supported GPH was formed via admixture between Northern Han Chinese and Southern TK people. We identified robust signatures associated with lipid metabolisms, such as fatty acid desaturases (FADS) and medically relevant loci associated with Mendelian disorder (GJB2) and complex diseases. We also explored the shared and unique selection signatures of ethnically different but linguistically related Guangxi lineages and found some shared signals related to immune and malaria resistance. CONCLUSIONS: Our genetic analysis illuminated the language-related fine-scale genetic structure and provided robust genetic evidence to support the admixture hypothesis that can explain the pattern of observed genetic diversity and formation of GPH. This work presented one comprehensive analysis focused on the population history and demographical adaptative process, which provided genetic evidence for personal health management and disease risk prediction models from Guangxi people. Further large-scale whole-genome sequencing projects would provide the entire landscape of southern Chinese genomic diversity and their contributions to human health and disease traits.
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Aclimatação , Genômica , Humanos , China , Alelos , IdiomaRESUMO
The prompt species identification from biological samples at a crime scene can rapidly filter out truly valuable biometric information for subsequent personal identification. Meanwhile, early sex determination can assist in narrowing the pool of suspects. However, the current methods for forensic DNA analysis, particularly in point-of-care scenarios, are often limited by the intricate equipment for signal generation and the laborious procedure for DNA purification. The present study introduces a novel portable lateral flow biosensor that possesses extraction-free and anti-aerosol characteristics for on-site determination of species and sex. The bloodstain can be directly submitted to loop-mediated isothermal amplification (LAMP) for the analysis of both mitochondrial and nuclear DNA. The incorporation of a lateral flow device with gold magnetic nanoparticle probes allows for visual interpretation of results through colorimetric signals while also preventing interference on result judgment from pigments such as hemoglobin. Carryover contamination, which is a disharmonious factor in LAMP, especially as the inherent contradiction derived from uncapping in the lateral flow strategy, has been effectively addressed through the integration of uracil DNA glycosylase without compromising the isothermy throughout the process. As a proof-of-concept experiment, species and sex can be accurately identified within 40 min from trace bloodstains amidst significant background interference by targeting cytochrome b and Y-chromosomal amelogenin. Furthermore, the single-blind study revealed a concordance rate of up to 100% in both simulative degraded and true dated bloodstains. This suggests that this biosensor has the potential to be utilized in forensic DNA analysis at crime scenes.
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RNA analysis has shown great value in forensic science, such as body fluids and tissue identification, postmortem interval estimation, biological age prediction, etc. Currently, most RNA follow-up experiments involve reverse transcription (RT) procedures. It has been shown that the RT step is variable and has a greater impact on subsequent data analysis, especially for forensic trace samples. However, the pattern of variation between different RNA template inputs and complementary DNA (cDNA) yield is unclear. In this study, a series of 2-fold gradient dilutions of RNA standards (1 µg/µL - 0.24 ng/µL) and forensic samples (including blood samples, saliva samples, bloodstains, and saliva stains) were reverse-transcribed using EasyQuick RT MasterMix. The obtained cDNA was quantified by droplet digital PCR (ddPCR) to assess the RT yield of the ACTB gene. The results showed that the 125 ng RNA template had the highest RT yield in a 10 µL RT reaction system with the selected kit. For all stain samples, the RT yield improved as the amount of RNA template input increased since RNA quantities were below 125 ng. As many commercialized reverse transcription kits using different kinds of enzymes are available for forensic RNA research, we recommend that systematic experiments should be performed in advance to determine the amount of RNA input at the optimum RT yield when using any kit for reverse transcription experiments.
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RNA , Humanos , RNA/genética , RNA/análise , Transcrição Reversa , Saliva/metabolismo , Saliva/química , Genética Forense/métodos , Genética Forense/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Padrões de Referência , DNA Complementar/genética , Manchas de Sangue , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normasRESUMO
The lack of a reliable and easy-to-operate screening pipeline for disease-related noncoding RNA regulatory axis is a problem that needs to be solved urgently. To address this, we designed a hybrid pipeline, disease-related lncRNA-miRNA-mRNA regulatory axis prediction from multiomics (DLRAPom), to identify risk biomarkers and disease-related lncRNA-miRNA-mRNA regulatory axes by adding a novel machine learning model on the basis of conventional analysis and combining experimental validation. The pipeline consists of four parts, including selecting hub biomarkers by conventional bioinformatics analysis, discovering the most essential protein-coding biomarkers by a novel machine learning model, extracting the key lncRNA-miRNA-mRNA axis and validating experimentally. Our study is the first one to propose a new pipeline predicting the interactions between lncRNA and miRNA and mRNA by combining WGCNA and XGBoost. Compared with the methods reported previously, we developed an Optimized XGBoost model to reduce the degree of overfitting in multiomics data, thereby improving the generalization ability of the overall model for the integrated analysis of multiomics data. With applications to gestational diabetes mellitus (GDM), we predicted nine risk protein-coding biomarkers and some potential lncRNA-miRNA-mRNA regulatory axes, which all correlated with GDM. In those regulatory axes, the MALAT1/hsa-miR-144-3p/IRS1 axis was predicted to be the key axis and was identified as being associated with GDM for the first time. In short, as a flexible pipeline, DLRAPom can contribute to molecular pathogenesis research of diseases, effectively predicting potential disease-related noncoding RNA regulatory networks and providing promising candidates for functional research on disease pathogenesis.
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MicroRNAs , RNA Longo não Codificante , Biologia Computacional , Redes Reguladoras de Genes , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Mensageiro/genéticaRESUMO
Devices of nanopore sequencing can be highly portable and of low cost. Thus, nanopore sequencing is promising in in-field forensic applications. Previous investigations have demonstrated that nanopore sequencing is feasible for genotyping forensic short tandem repeats (STRs) by using sequencers of Oxford Nanopore Technologies. Recently, Qitan Technology launched a new portable nanopore sequencer and became the second supplier in the world. Here, for the first time, we assess the QNome (QNome-3841) for its accuracy in nanopore sequencing of STRs and compare with MinION (MinION Mk1B). We profile 54 STRs of 21 unrelated individuals and 2800M standard DNA. The overall accuracy for diploid STRs and haploid STRs were 53.5% (378 of 706) and 82.7% (134 of 162), respectively, by using QNome. The accuracies were remarkably lower than those of MinION (diploid STRs, 84.5%; haploid, 90.7%), with a similar amount of sequencing data and identical bioinformatics analysis. Although it was not reliable for diploid STRs typing by using QNome, the haploid STRs were consistently correctly typed. The majority of errors (58.8%) in QNome-based STR typing were one-repeat deviations of repeat units in the error from true allele, related with homopolymers in repeats of STRs.
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In paternity testing, short tandem repeats (STRs) allele mismatches are often detected. Nowadays, polymerase chain reaction- and capillary electrophoresis (CE)-based STR genotyping is the most commonly used method to distinguish alleles based on their length. However, it could not detect alleles of the same size with sequence differences. Massively parallel sequencing (MPS) can determine not only allele sizes but also sequences, which could explain the causes of allele mismatches. Additionally, more types of genetic markers can be detected in a single assay, which increases the discriminatory power and facilitates the analysis of paternity tests. In this study, we analyzed 11 cases with homozygous allele mismatches from routine DNA trio paternity tests using the CE platform. Samples were sequenced using the ForenSeq DNA Signature Prep Kit and the MiSeq FGx Sequencing System. The results show that of the eight father-child mismatch cases and three mother-child mismatch cases, five cases with D5S818 and D8S1179 and one case at D13S317 were classified as non-amplification. The other three cases and two cases could be defined as mutations. This study suggests that MPS-based STR genotyping can provide additional information that allows more accurate interpretation of allelic mismatches in paternity testing.
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Impressões Digitais de DNA , Paternidade , Humanos , Impressões Digitais de DNA/métodos , Alelos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Repetições de Microssatélites/genética , DNARESUMO
Nanopore sequencing technology has broad application prospects in forensic medicine due to its small size, portability, fast speed, real-time result analysis capabilities, single-molecule sequencing abilities, and simple operation. Here, we demonstrate for the first time that nanopore sequencing platforms can be used to identify individuals in the field. Through scientific and reasonable design, a nanopore MinION MK1B device and other auxiliary devices are integrated into a portable detection box conducive to individual identification at the accident site. Individual identification of 12 samples could be completed within approximately 24 h by jointly detecting 23 short tandem repeat (STR) loci. Through double-blinded experiments, the genotypes of 49 samples were successfully determined, and the accuracy of the STR genotyping was verified by the gold standard. Specifically, the typing success rate for 1150 genotypes was 95.3%, and the accuracy rate was 86.87%. Although this study focused primarily on demonstrating the feasibility of full-process testing, it can be optimistically predicted that further improvements in bioinformatics workflows and nanopore sequencing technology will help enhance the feasibility of Oxford Nanopore Technologies equipment for real-time individual identification at accident sites.
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Repetições de Microssatélites , Sequenciamento por Nanoporos , Humanos , Repetições de Microssatélites/genética , Sequenciamento por Nanoporos/métodos , Genética Forense/métodos , Projetos Piloto , Reprodutibilidade dos Testes , Genótipo , Análise de Sequência de DNA/métodos , Impressões Digitais de DNA/métodos , Desenho de EquipamentoRESUMO
Blood-containing mixtures often appear in murder and robbery cases, and their identification plays a significant role in solving crimes. In recent years, the co-detection of DNA methylation markers (CpG) and single nucleotide polymorphism (SNP) markers has been shown to be a promising tool for the identification of semen and its donor. However, similar research on blood stains that are frequently found at crime scenes has not yet been reported. In this study, we employed blood-specific CpG-linked SNP markers (CpG-SNP) for blood-specific genotyping and the linking of blood and its donor. The tissue-specific CpG markers were screened from the literature and further verified by combining bisulfite conversion with amplification-refractory mutation system (ARMS) technology. Meanwhile, adjacent SNP markers with a minor allele frequency (MAF) greater than 0.1 were selected within 400 bp upstream and downstream of the CpG markers. SNP genotyping was performed using SNaPshot technology on a capillary electrophoresis (CE) platform. Finally, a multiplex panel, including 19 blood-specific CpG linked to 23 SNP markers, as well as 1 semen-specific CpG, 1 vaginal secretion-specific CpG, and 1 saliva-specific CpG marker, was constructed successfully. The panel showed good tissue specificity and blood stains stored at room temperature for up to nine months and moderately degraded (4 < DI < 10) could be effectively identified. Moreover, it could also be detected when blood content in the mixed stains was as low as 1%. In addition, 15 ng of DNA used for bisulfite conversion was required for obtaining a complete profile. The cumulative discrimination power of the panel among the Han population of northern China could reach 0.999983. This is the first investigation conducted for the simultaneous identification of blood and its donor regardless of other body fluids included in mixed stains. The successful construction of the panel will play a vital role in the comprehensive analysis of blood-containing mixtures in forensic practice.
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Líquidos Corporais , Polimorfismo de Nucleotídeo Único , Feminino , Humanos , Sulfitos , Saliva , Metilação de DNA , Marcadores Genéticos , Genética Forense/métodosRESUMO
The construction of a fluorescence aptamer sensor was achieved by employing the fundamental principle of fluorescence resonance energy transfer. By employing molecular modeling technologies to identify the binding site, the high-affinity aptamer APT-40nt was derived from the whole sequence and utilized on the graphene oxide (GO) fluorescent platform for the purpose of achieving a highly sensitive detection of methamphetamine (METH). The aptamer tagged with fluorescein (FAM) dye undergoes quenching in the presence of GO due to π-stacking interaction. With the addition of the target, the aptamer that has been tagged was detached from the GO surface, forming a stable complex with METH. This process resulted in fluorescence restoration of the system, and the degree of fluorescence restoration was proportional to METH concentration in the linear range of 1-50 and 50-200 nM. Notably, under optimized conditions, the detection limit of this aptasensor was as low as 0.78 nM, which meets the detection limit requirements of METH detection in saliva and urine in some countries and regions. Moreover, other common illicit drugs and metabolites had minimizing interference with the determination. The established aptasensor, therefore, has been successfully applied to detect METH in saliva and urine samples and exhibited satisfactory recoveries (87%-111%). This aptasensor has the advantages of low detection limit, excellent selectivity, ease of operation, and low cost, providing a promising strategy for on-site detection of METH in saliva and urine.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Metanfetamina , Óxidos/química , Limite de Detecção , Técnicas Biossensoriais/métodos , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Grafite/químicaRESUMO
In recent years, with the continuous progress of DNA extraction and detection technology, cell-free DNA(cfDNA)has been widely used in the life science field, and its potential application value in forensic identification is becoming more and more obvious. This paper reviews the concept, formation mechanism, and classification of cfDNA, etc., and describes the latest research progress of cfDNA in personal identification of crime scene touch DNA samples and non-invasive prenatal paternity testing (NIPPT). Meanwhile, this paper summarizes the potential application of cfDNA in injury inference, and discusses the advantages and disadvantages of common cfDNA analysis methods and techniques, and its application prospects, to provide a new idea for the wide application of cfDNA in the field of forensic science.
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Ácidos Nucleicos Livres , Gravidez , Feminino , Humanos , Ácidos Nucleicos Livres/genética , Paternidade , Ciências Forenses , Tato , DNA/genéticaRESUMO
OBJECTIVES: To explore the context and hotspot changes of forensic mixed stain research through bibliometric approach. METHODS: The literature of forensic mixed stain included in the core collection of Web of Science database from 2011 to 2022 were collected as the study object, and the annual publication number, countrie (region), institution, journal, keywords, etc. were bibliometrically and visually analyzed using the R-based Bibliometrix 1.1.6 package and VOSviewer 1.6.18 software. RESULTS: A total of 732 articles on forensic mixed stain were included from 2011 to 2022, with the annual number of articles published and the annual citation frequency showing a steady increase year by year. Among the 59 countries (regions) with the most published articles, the United States ranked first with 246 articles, followed by China with 153 articles. The literature came from 104 journals, and the total number of articles published in the top 10 journals was 633. FORENSIC SCI INT GENET ranked first with 307 articles. Visual analysis using VOSviewer software showed that keywords could be divided into four research clusters, namely the genetic marker development group (blue), the mixed stain typing analysis theory group (red), the sequencing analysis group (yellow), and the case sample research group (green). It can be divided into four development stages in terms of different time periods: early development (2011-2013), middle development (2014-2016), rapid development (2017-2020) and latest development (2021-2022). CONCLUSIONS: The number of publications by domestic and foreign scholars in the study of mixed stain in forensic science is showing a relatively stable trend. Machine learning, next generation sequencing and other research have been the hottest topics that have attracted the most attention in recent years, which is expected to further develop the theory of mixed stain typing and sequencing analysis in forensic mixed stain research.
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Bibliometria , Corantes , China , Ciências Forenses , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
The use of DNA methylation to predict chronological age has shown promising potential for obtaining additional information in forensic investigations. To date, several studies have reported age prediction models based on DNA methylation in body fluids with high DNA content. However, it is often difficult to apply these existing methods in practice due to the low amount of DNA present in stains of body fluids that are part of a trace material. In this study, we present a sensitive and rapid test for age prediction with bloodstains based on pyrosequencing and random forest regression. This assay requires only 0.1 ng of genomic DNA and the entire procedure can be completed within 10 h, making it practical for forensic investigations that require a short turnaround time. We examined the methylation levels of 46 CpG sites from six genes using bloodstain samples from 128 males and 113 females aged 10-79 years. A random forest regression model was then used to construct an age prediction model for males and females separately. The final age prediction models were developed with seven CpG sites (three for males and four for females) based on the performance of the random forest regression. The mean absolute deviation was less than 3 years for each model. Our results demonstrate that DNA methylation-based age prediction using pyrosequencing and random forest regression has potential applications in forensics to accurately predict the biological age of a bloodstain donor.
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Metilação de DNA , Algoritmo Florestas Aleatórias , Masculino , Feminino , Humanos , Metilação de DNA/genética , Genética Forense/métodos , Ilhas de CpG/genética , Análise de Sequência de DNA/métodos , DNA/genética , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
Hair is one of the most common pieces of biological evidence found at a crime scene and plays an essential role in forensic investigation. Hairs, especially non-follicular hairs, are usually found at various crime scenes, either by natural shedding or by forcible shedding. However, the genetic material in hairs is usually highly degraded, which makes forensic analysis difficult. As a result, the value of hair has not been fully exploited in forensic investigations and trials. In recent years, with advances in molecular biology, forensic analysis of hair has achieved remarkable strides and provided crucial clues in numerous cases. This article reviews recent developments in DNA and protein analysis of hair and attempts to provide a comprehensive solution to improve forensic hair analysis.
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DNA , Genética Forense , Humanos , DNA/genética , Cabelo , Medicina Legal , Crime , DNA Mitocondrial/genéticaRESUMO
Identification of body fluids is critical for crime scene reconstruction, and a source of investigation source of investigative leads. In recent years, microbial DNA analysis using sequencing and quantitative real-time polymerase chain reaction have been used to identify body fluids. However, these techniques are time-consuming, expensive, and require complex workflows. In this study, a new method for simultaneous detection of Streptococcus salivarius and Lactobacillus crispatus using polymerase chain reaction (PCR) in combination with a lateral flow dipstick (LFD) was developed to identify saliva and vaginal fluid in forensic samples. LFD results can be observed with the naked eye within 3 min with a sensitivity of 0.001 ng/µL DNA. The PCR-LFD assay was successfully used to detect S. salivarius and L. crispatus in saliva and vaginal fluid respectively, and showed negative results in blood, semen, nasal fluid, and skin. Moreover, saliva and vaginal fluid were detectable even at an extremely high mixing ratio of sample DNA (1:999). Saliva and vaginal fluid were identified in various mock forensic samples. These results indicate that saliva and vaginal fluid can be effectively detected by identifying S. salivarius and L. crispatus, respectively. Furthermore, we have shown that DNA samples used to identify saliva and vaginal fluid can also provide a complete short tandem repeat (STR) profile when used as source material for forensic STR profiling. In summary, our results suggest that PCR-LFD is a promising assay for rapid, simple, reliable, and efficient identification of body fluids.
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Líquidos Corporais , Saliva , Feminino , Humanos , Saliva/microbiologia , Sêmen , DNA , Reação em Cadeia da Polimerase em Tempo Real , Bactérias , Genética ForenseRESUMO
In forensic investigations, age estimation is vital for determining whether a suspect is under or over the legally defined adult age. With breakthroughs in RNA sequencing technology, small noncoding RNAs have provided new ways to solve problems related to the age estimation of trace or aged samples, owing to their small molecular weight and better stability. In our previous study, we had applied miRNAs for the age estimation of bloodstains; however, further improvement of the existing model is needed. PIWI-interacting RNAs (PiRNAs), which are 24-32 nt noncoding small RNA molecules involved in the PIWI-piRNA pathway, play an important role in the aging process. In this study, we explored the possibility of simultaneously analyzing piRNAs and miRNAs for better age estimation purpose. Through massively parallel sequencing, five age-related piRNAs were identified in blood samples that had been stored for eight years. Further real-time PCR analysis revealed that two piRNAs (piR-000753 and piR-020548) showed relatively higher efficiency in age estimation. Additionally, two age-related miRNAs (miR-324-3p and miR-330-5p) were used to build the estimation model. Among all algorithms tested, gradient boosting showed the lowest mean absolute error (MAE) and root mean square error (RMSE) values (3.171 and 4.403 years, respectively) for the validation dataset (n = 110). The errors of the model were less than 5 years and 10 years for 81.82% and 96.36% of the samples, respectively. The results suggest that the combined use of piRNA and miRNA markers may increase the accuracy of age estimation, and our new model has great potential for application in forensic casework.
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Manchas de Sangue , MicroRNAs , Pequeno RNA não Traduzido , Humanos , Adulto , Idoso , Criança , MicroRNAs/genética , RNA de Interação com Piwi , RNA Interferente Pequeno/genéticaRESUMO
Talent is one of the basic and strategic supports for building a modern socialist country in all aspects. Since the 1980s, the establishment of forensic medicine major and the cultivation of innovative talents in forensic medicine have become hot topics in higher education in forensic medicine. Over the past 43 years, the forensic medicine team of Shanxi Medical University has adhered to the joint education of public security and colleges, and made collaborative innovation, forming a training mode of "One Combination, Two Highlights, Three Combinations, Four in One" for innovative talents in forensic medicine. It has carried out "5+3/X" integrated reform, and formed a relatively complete talent training innovation mode and management system in teaching, scientific research, identification, major, discipline, team, platform and cultural construction. It has made a historic contribution to China's higher forensic education, accumulated valuable experience for the construction of first-class major and first-class discipline of forensic medicine, and provided strong support for the construction of the national new forensic talent training system. The popularization of this training mode is conducive to the rapid and sustainable development of forensic science, and provides more excellent forensic talents for national building, regional social development and the discipline construction of forensic science.
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Medicina Legal , Humanos , Medicina Legal/educação , AptidãoRESUMO
We experimentally study the interference of dipole scattered light from two optically levitated nanoparticles in vacuum, which present an environment free of particle-substrate interactions. We illuminate the two trapped nanoparticles with a linearly polarized probe beam orthogonal to the propagation of the trapping laser beams. The scattered light from the nanoparticles are collected by a high numerical aperture (NA) objective lens and imaged. The interference fringes from the scattered vector light for the different dipole orientations in image and Fourier space are observed. Especially, the interference fringes of two scattered light fields with polarization vortex show the π shift of the interference fringes between inside and outside the center region of the two nanoparticles in the image space. As far as we know, this is the first experimental observation of the interference of scattered vector light fields from two dipoles in free space. This work also provides a simple and direct method to determine the spatial scales between optically levitated nanoparticles by the interference fringes.
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Insertion/deletion markers (InDels) become an important marker for forensic medicine because of their compatible typing techniques with STRs and lower mutation rates. Recent years, a new kind of DNA marker named Multi-InDel was reported as characterized by two or more tightly linked InDel loci within a short length of physical position, usually 200-300 nucleotides. Many pieces of research showed that Multi-InDels had excellent application values in ancestry inference and forensic medicine. Since the identical number of insertion/deletion nucleotides of the InDel markers that composing the Multi-InDel marker, the genotypes of most reported Multi-InDels could not be directly typed by capillary electrophoresis (CE) due to the lack of length discrepancy among the composing InDel sequence. In this study, we applied a typing system of 20 Multi-InDels including 41 InDels, whose genotypes could be deduced by CE and assessed their potential applications in forensic medicine. A total of 200 unrelated Chinese Han individuals and five mother-child-father trios with proven paternity with one STR locus transmission incompatibilities from Shanxi province were genotyped by the multiplex system. The results showed that a total of 70 specific alleles were observed, more than three alleles were observed in 19 loci and seven alleles were observed in one locus. The combined probability of exclusion and the combined power of discrimination were 0.992 and 0.99999999993, respectively. This study demonstrates their potential usefulness for individual identification and paternity tests. The development of Multi-InDels provided another genetic tool inherent in higher polymorphic and lower mutation rates.