With the advance of molecular biology, DNA analysis technology has been widely applied in forensic science. Non-human DNA analysis can be used in some special cases and has unique forensic value to provide investigation clues and trial basis. Animal DNA typing plays a more prominent role in the detection of all kinds of non-human DNA related cases and is the main content of forensic non-human DNA analysis. This paper reviews the development history, present situation, advantages and disadvantages of animal DNA typing according to its technology, characteristic, challenges facing forensic science application scenarios, and also its future development.
Animals ; DNA Fingerprinting ; Forensic Medicine ; DNA/analysis* ; Forensic Sciences ; Molecular Biology ; Forensic Genetics

Given the complexity of biological samples and the trace nature of target materials in forensic trace analysis, a simple and effective method is needed to obtain sufficient target materials from complex substrates. Magnetic nanoparticles (MNPs) have shown a wide range of application value in many research fields, such as biomedicine, drug delivery and separation, due to their unique superparamagnetic properties, stable physical and chemical properties, biocompatibility, small size, high specific surface area and other characteristics. To apply MNPs in the pretreatment of forensic materials, maximize the extraction rate of the target materials, and minimize interference factors to meet the requirements of trace analysis of the target materials, this paper reviews the application of MNPs in the fields of forensic toxicological analysis, environmental forensic science, trace evidence analysis and criminal investigation in recent years, and provides research ideas for the application of MNPs in forensic trace analysis.
Magnetite Nanoparticles/chemistry* ; Forensic Medicine ; Forensic Sciences ; Forensic Toxicology

OBJECTIVES: To survey the development status and actual needs of virtual autopsy technology in China and to clarify the applicability of forensic virtual autopsy laboratory accreditation. METHODS: The questionnaire was set up included three aspects：(1) the current status of virtual autopsy technology development; (2) the accreditation elements such as personnel, equipment, entrustment and acceptance, methods, environmental facilities; (3) the needs and suggestions of practicing institutions. A total of 130 forensic pathology institutions were surveyed by online participation through the Questionnaire Star platform. RESULTS: Among the 130 institutions, 43.08% were familiar with the characteristics of virtual autopsy technology, 35.38% conducted or received training in virtual autopsy, and 70.77% have establishment needs (including maintenance). Relevant elements were suitable for laboratory accreditation. CONCLUSIONS Virtual autopsy identification has gained social recognition. There is a demand for accreditation of forensic virtual autopsy laboratory. After the preliminary assessment, considering the characteristics and current situation of this technology, China National Accreditation Service for Conformity Assessment (CNAS) can first carry out the accreditation pilot of virtual autopsy project at large comprehensive forensic institutions with higher identification capability, and then CNAS can popularize the accreditation in a wide range when the conditions are suitable.
Autopsy ; Forensic Medicine ; Forensic Pathology ; Accreditation ; Surveys and Questionnaires

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.
Humans ; Forensic Medicine/education* ; Aptitude

Tri-allelic pattern in autosomal STR is a common abnormal typing phenomenon in forensic DNA analysis, which brings difficulties and uncertainties to the evaluation of the evidence weight in actual cases. This paper reviews the types, formation mechanism, occurrence frequency, genetic pattern and quantitative evaluation of evidence of the tri-allelic pattern in autosomal STR in forensic DNA analysis. This paper mainly explains the formation mechanism and genetic patterns based on different types of tri-allelic pattern. This paper also discusses the determination of tri-allelic pattern and the quantitative method of evidence evaluation in paternity testing and individual identification. This paper aims to provide references for scientific and standardized analysis of this abnormal typing phenomenon in forensic DNA analysis.
Alleles ; DNA/genetics* ; Forensic Medicine ; Gene Frequency ; Microsatellite Repeats ; Humans

OBJECTIVES: To analyze the gross pathological data of sudden cardiac death (SCD) with different causes, to provide data support for the identification of sudden cardiac death with unknown causes. METHODS: A total of 167 adult SCD cases in the archive of the Forensic Expertise Institute of Nanjing Medical University from 2010 to 2020 were collected. The gross pathological data of SCD cases were summarized and the characteristics of different causes of death were statistically analyzed. RESULTS: The ratio of male to female SCD cases was 3.4∶1. Coronary heart disease was the leading cause of SCD, and mainly distributed in people over 40 years old. SCD caused by myocarditis was mainly distributed in young people and the mean age of death was (34.00±9.55) years. By analyzing the differences in cardiac pathological parameters of SCD with different causes, it was found that the aortic valve circumference was significantly dilated in the SCD caused by aortic aneurysm or dissection (P<0.05). The heart weight of SCD caused by aortic aneurysm or dissection and combined factors was greater, and both pulmonary and tricuspid valvular rings were dilated in the SCD caused by combined factors in adult males (P<0.05). CONCLUSIONS Various gross pathological measures of SCD with different causes are different, which has reference value in the cause of death identification of SCD.
Humans ; Adult ; Male ; Female ; Adolescent ; Young Adult ; Death, Sudden, Cardiac/pathology* ; Coronary Disease ; Heart ; Forensic Medicine ; Autopsy

OBJECTIVES: To realize the dynamic visualization of forensic odontology based on the bibliometrics methods, and capture the research hotspots and identify the future development trend. METHODS: Literature articles published from January 1995 to December 2020 were searched according to specific subject words in the core data set of Web of Science. The visualization analysis of publishing country, institution, discipline, author, co-cited journal and keywords was performed by CiteSpace 5.7.R5W software. RESULTS: The annual analysis of publications showed an upward trend of forensic odontology research literature year by year, with the number of annual publications more than 110 in the last five years. Developed countries were the main source of contributions and the average centrality was greater than 0.2. The research of forensic odontology involved multiple disciplines, including stomatology, biology, computer science and medical imaging, with a distinct interdisciplinary feature. A total of 115 nodes were obtained by keyword cluster analysis. The principal line of forensic odontology mainly included individual identification and age estimation and the emergence of hotspots was closely related to new technologies. Population-based odontology investigation, improvement of traditional dental age estimation method and dental age estimation based on new technology were popular research in forensic odontology. CONCLUSIONS Developing countries urgently need to increase the focus on related research. It may be an important direction for the development of forensic odontology to establish and enrich the regional dental database, develop new odontology identification technology combined with frontier and high-end technology, and develop the identification program based on advanced information technology.
Forensic Medicine ; Software ; Bibliometrics

OBJECTIVES: To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy. METHODS: The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta^® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types. RESULTS: According to the results of data training and comparison, all the recognition accuracies of Fanta^®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy. CONCLUSIONS Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.
Humans ; Forensic Medicine/methods* ; Coloring Agents/analysis* ; Coffee ; Spectrometry, Fluorescence ; Body Fluids/chemistry*

OBJECTIVES: To compare the effects of cell lysis method and magnetic beads method in forensic DNA identification and to explore these two methods in forensic DNA identification. METHODS: The genome DNA of THP-1 cells in different quantities was extracted by the cell lysis method and magnetic beads method, and the DNA content was quantified by real-time quantitative PCR. The cell lysis method and magnetic beads method were used to type the STR of human blood with different dilution ratios. RESULTS: When the numbers of THP-1 cell were 100, 400 and 800, the DNA content extracted by cell lysis method were (1.219±0.334), (5.081±0.335), (9.332±0.318) ng, respectively; and the DNA content extracted by magnetic beads method were (1.020±0.281), (3.634±0.482), (7.896±0.759) ng, respectively. When the numbers of THP-1 cells were 400 and 800, the DNA content extracted by the cell lysis method was higher than that by the magnetic beads method. The sensitivity of cell lysis method and magnetic beads method was similar in STR typing of human blood at different dilution ratios. Complete STR typing could be obtained at 100, 300 and 500-fold dilutions of blood samples, but could not be detected at 700-fold dilution. STR typing of undiluted human blood could not be detected by cell lysis method. CONCLUSIONS The cell lysis method is easy to operate and can retain template DNA to the maximum extend. It is expected to be suitable for trace blood evidence tests.
Humans ; Forensic Medicine ; DNA/genetics* ; Real-Time Polymerase Chain Reaction ; Magnetic Phenomena ; DNA Fingerprinting/methods* ; Microsatellite Repeats

With the improvement of DNA methylation detection techniques, studies on age-related methylation sites have found more age-specific ones across tissues, which improves the sensitivity and accuracy of age estimation. In addition, the establishment of various statistical models also provides a new direction for the age estimation of tissues from different sources. This review summarizes the related studies of age estimation based on DNA methylation from the aspects of detection technology, age-related cytosine phosphate guanine site and model selection in recent years.
DNA Methylation ; Forensic Genetics/methods* ; CpG Islands ; Forensic Medicine