A Bibliometric and Visual Analysis of the Current Status and Trends of Foren-sic Mixed Stain Research / 法医学杂志

Objective 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 col-lection of Web of Science database from 2011 to 2022 were collected as the study object,and the an-nual 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.Re-sults A total of 732 articles on forensic mixed stain were included from 2011 to 2022,with the an-nual 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 peri-ods:early development(2011-2013),middle development(2014-2016),rapid development(2017-2020)and latest development(2021-2022).Conclusion 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.

Analysis of Genetic Polymorphism and Population Genetic Structure of 57 Autosomal InDel Loci in Beichuan Qiang Population / 法医学杂志

OBJECTIVES@#To investigate the genetic information of 57 autosomal InDel loci (A-InDels) included in AGCU InDel 60 fluorescence detection kit in the Beichuan Qiang population of Sichuan Province and evaluate its application value in forensic medicine.@*METHODS@#A total of 200 unrelated healthy individuals from Beichuan Qiang population of Sichuan Province were typing detected by AGCU InDel 60 fluorescence detection kit. Allele frequencies and population genetic parameters of the 57 A-InDels were statistically analyzed and compared with the available data of 26 populations.@*RESULTS@#After Bonferroni correction, there was no linkage disequilibrium between the 57 A-InDels, and all loci were in Hardy-Weinberg equilibrium. Except for rs66595817 and rs72085595, the minor allele frequencies of 55 A-InDels were above 0.3. PIC ranged from 0.298 3 to 0.375 0, CDP was 1-2.974 8×10-24, CPEduo was 0.999 062 660, and CPEtrio was 0.999 999 999. The calculation of the genetic distance showed that Beichuan Qiang population had the closest genetic distances with Beijing Han and South China Han populations, but far away from African populations.@*CONCLUSIONS@#The 57 A-InDels in AGCU InDel 60 fluorescence detection kit have a good genetic polymorphism in Beichuan Qiang population of Sichuan Province, which can be used as effective supplemental for individual identification and paternity identification in forensic medicine.

Geolocation Inference of Forensic Individual Origin by Soil Metagenomic Analysis / 法医学杂志

Objective To preliminarily discuss the feasibility of geolocation inference of forensic individual origin by soil metagenomic analysis. Methods The 33 soil samples from Heilongjiang, Qinghai and Tibet were collected, total bacterial DNA in the samples were extracted, and universal primers were used to amplify the V3 and V4 hypervariable region of bacterial 16S rDNA. The region was sequenced by high-throughput sequencing （HTS） with the MiSeq sequencer. Bioinformatics analysis such as species composition and sample comparison was performed on sequencing data. The richness index and diversity index were calculated based on operational taxonomic unit （OTU） results. Results A total of 2 720 149 sequences were generated by sequencing. Those sequences were clustered into 114 848 OTUs. The Chao1 indexes of soil microorganisms in Heilongjiang, Qinghai, and Tibet were 797.45, 745.11 and 535.98, respectively, and Shannon indexes were 6.46, 6.36 and 6.25, respectively. The number of bacterial species and the community diversity in the soil from high to low were Heilongjiang > Qinghai > Tibet. The composition of soil bacteria in three provinces at various classification levels were obtained, the dominant genuses in Heilongjiang were Chthoniobacteraceae DA101 and an unannotated genus of Thermogemmatisporaceae; the dominant genuses in Qinghai were an unannotated genus of Cytophagaceae and an unannotated genus of Nocardioidaceae; the dominant genuses in Tibet were an unannotated genus of Comamonadaceae and Verrucomicrobiaceae Luteolibacter. The results of principal co-ordinates analysis demonstrated that, according to the weighted UniFrac analysis, the three principle components represented 56.36% of the total variable, and according to the unweighted UniFrac analysis, the three principle components represented 34.81% of the total variable. The samples from the same province could be clustered together, and the species and content of soil microorganisms from different provinces were significantly different. Conclusion Based on the metagenomic analysis method, soil samples from different regions can be effectively distinguished, which has potential application value in geolocation inference of forensic individual origin in the future.