Traceability of Geographic Origin Using Human Skin and Oral Microbiota / 法医学杂志

OBJECTIVES@#To explore the possibility of using human skin and oral microorganisms to estimate the geographic origin of an individual through the sequencing analysis of bacterial 16S rRNA gene.@*METHODS@#Microbial DNA was extracted from the palm and oral microorganisms of the Han population in Shanghai and Chifeng, Inner Mongolia, and the composition and diversity of the microbiota were analyzed by full-length 16S rRNA gene sequencing. Then, differential species were screened and a geographic location prediction model was constructed.@*RESULTS@#The compositions of palm and oral microorganisms between Shanghai and Chifeng samples were both different. The abundance and uniformity of palm side skin microorganisms were higher in Chifeng samples than in Shanghai samples, while there was no significant difference in oral microorganisms. Permutational multivariate analysis of variance (PERMANOVA) confirmed that the β-diversity between the samples from the two places were statistically significant, and the coefficients of determination (R2) for skin and oral samples were 0.129 and 0.102, respectively. Through principal co-ordinates analysis (PCoA), the samples from the two places could be preliminarily distinguished. The predictive model had the accuracies of 0.90 and 0.83 for the geographic origin using the skin and oral samples, respectively.@*CONCLUSIONS@#There are differences in the compositions of palm and oral microbiota between Han populations in Shanghai and Chifeng. The prediction model constructed by the random forest algorithm can trace the unknown individuals from the above two places.

Polymorphism and Forensic Application Value of 71 Y-SNP Loci in Han Population of Northwest China / 法医学杂志

OBJECTIVES@#To analyze the polymorphism of 71 SNP loci on Y chromosome in Han population of Northwest China, to assess its forensic application value, and to screen out Y-SNP loci for forensic examination of Han population in East, South, and Northwest China based on the integration of previous research results.@*METHODS@#Multiplex polymerase chain reaction （PCR） and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） were performed on 71 Y-SNP loci of 202 unrelated Han male individuals in Northwest China. Gene diversity （GD） and haplotype diversity （HD） values were calculated, and then Y-SNP loci of Han population in East, South, and Northwest China were screened with the combination of data from previous research.@*RESULTS@#Among the detected 71 loci, 67 loci were polymorphic in the Northwest Han male population, with GD values 0.010 0-0.502 2. There were 22 and 25 loci with a moderate （0.2≤GD<0.3） and high （GD≥0.3） amount of genetic information, respectively. There were 26 loci for the Han communities in Northwest, South, and East China.@*CONCLUSIONS@#Y-SNP loci are potential in paternity testing and individual identification, as well as the judgement of population distribution and migration.

Assessment on Application of 24 Y-STR Loci in Forensic Science / 法医学杂志

OBJECTIVES@#To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application.@*METHODS@#The 24 Y-STR loci were tested by self-built fluorescent multiplex system, and the forensic assessment was conducted by 139 pairs of father-son samples collected in Jinan, Shandong province.@*RESULTS@#Totally 176 alleles were identified among the 24 Y-STR loci in the sample of 139 unrelated individuals labeled with father, and the gene diversity （GD） distributed between 0.083 7 （DYS645）-0.966 9 （DYS385a/b）. According to the 24 Y-STR loci, 139 different haplotypes were detected from 139 unrelated male individuals labeled with father in Han population of Shandong province and with no shared haplotype observed. The overall haplotype diversity （HD） was 1 and the discrimination capacity （DC） was 1. A total of 5 one-step mutations events were observed among the 24 Y-STR loci in 139 pairs of father-son. The average mutation rate was 0.001 5 [95% CI （0.000 5, 0.003 5）].@*CONCLUSIONS@#The system of 24 Y-STR loci shows a strong individual recognition ability and low mutation rate in the population in Jinan, Shandong province, and it has good application value in forensic science.

Sixty-six Biallelic Genetic Markers on Y chromosome by MALDI-TOF-MS / 法医学杂志

OBJECTIVES@#To analyse the genetic polymorphisms of 66 biallelic genetic markers on Y chromosome in Eastern Chinese Han population, and evaluate their values in forensic application.@*METHODS@#Genotyping of 66 biallelic genetic markers on Y chromosome was studied in 205 unrelated males of Eastern Chinese Han population by multiplex PCR combined matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. The allele frequencies on the loci to be tested were calculated by direct counting method, and the gene diversity （GD） and haplotype diversity （HD） were calculated by corresponding formulas. The haplotypes of this system were tested by software Arlequin v3.5.2.2 and the comparison of population genetics were analyzed.@*RESULTS@#A total of 60 biallelic genetic markers on Y chromosome were polymorphic in males of Eastern Chinese Han population, and the ranges of GD were from 0.038 5 to 0.501 9. Eighty-five different haplotypes were observed and the HD was 0.970 3. The differences of partial SNP loci between the Han population of Eastern China and that of Xinjiang and Guangdong were statistically significance.@*CONCLUSIONS@#Sixty biallelic genetic markers and the detection system can complementally provide genetic information in kinship testing and individual identification. The MALDI-TOF-MS technology is able to type biallelic genetic markers.

Population Difference Analysis of Allele Frequencies of 24 Y-STR Loci / 法医学杂志

OBJECTIVES@#To investigate the population genetic polymorphisms of 24 Y-STR loci in unrelated individuals in Eastern Chinese Han population, and to compare the difference of Han group between Eastern China and Guangdong.@*METHODS@#The population genetics of 24 Y-STR loci in 268 unrelated Han individuals from Eastern China were analyzed by GFS 24 Y-STR amplification kit. The allele frequencies in Eastern Chinese Han population were compared with the data in Guangdong Han population, and the difference analysis between two groups was performed.@*RESULTS@#Among the 24 Y-STR loci of 268 unrelated Han individuals from Eastern China, 235 alleles and 267 haplotypes were observed. GD value ranged from 0.564 9 to 0.966 8. The difference between 12 loci （DYS622, DYS552, DYS443, et al.） of Han population in Eastern China and in Guangdong was statistically significance.@*CONCLUSIONS@#GFS 24Y STR amplification system shows favorable polymorphisms, which can be used in patrilineal genetic relationship identification.

Genetic Polymorphisms of 26 Y-STR Loci in Fujian She Nationality and Its Forensic Application / 法医学杂志

OBJECTIVE@#To study the forensic application of Goldeneye DNA ID 26Y Kit in the She nationality.@*METHODS@#Through capillary electrophoresis, the genotype of 26 Y-STR loci were analyzed in 53 unrelated male individuals from Fujian She nationality. The population genetics parameters such as allele frequency and haplotype diversity were calculated. The comparisons among the She nationality and the other nationalities were analyzed.@*RESULTS@#A total of 126 alleles were observed on the 26 Y-STR loci of 53 unrelated male individuals. The allele frequencies and GD value ranged from 0.010 1 to 0.886 8 and 0.211 2 to 0.846 2, respectively. The GD value was greater than 0.5 in the 19 loci. A total of 47 haplotypes were observed. Based on R(ST), multidimensional scaling plot indicated that the genetic relationship among Fujian She nationality and Minnan Han nationality was closest, followed by Southern China Han nationality and Northern China nationality.@*CONCLUSION@#Goldeneye™ DNA ID 26Y Kit including 26 Y-STR loci has good polymorphism in the She nationality. As an additional system, it has forensic application value in some special cases.

Forensic application of 30 InDel loci in Han and She nationalities of Eastern China / 法医学杂志

OBJECTIVE@#To evaluate the forensic application value of 30 insertion/deletion (InDel) loci included in Investigator DIPplex Kit in Han and She nationalities of Eastern China.@*METHODS@#A total of 565 unrelated individuals in Han nationality and 119 ones in She nationality of Eastern China were investigated using Investigator DIPplex Kit. Allele frequencies, population genetics parameters of the 30 InDel loci were statistically calculated.@*RESULTS@#In Han nationality, the mean Ho was 0.413 3, the mean DP was 0.551 1, the mean PIC was 0.320 0. And in She nationality, the mean Ho was 0.389 6, the mean DP was 0.543 3, the mean PIC was 0.310 0. No deviation from Hardy-Weinberg equilibrium was observed in Han and She nationalities (P > 0.05).@*CONCLUSION@#The 30 loci in Investigator DIPplex Kit show good genetic diversity in Han and She nationalities, and could be used as a supplemental tool for some special paternity cases.

Linkage disequilibrium and mutation rate analysis of sixteen X-STR loci / 法医学杂志

OBJECTIVE@#To assess the patterns of linkage disequilibrium (LD) of 16 STR loci on X chromo- some and investigate the genetic stability.@*METHODS@#Genomic DNA samples extracted from blood stains from 500 unrelated individuals and 885 lineage members from Eastern Chinese Han population were genotyped through multiplex amplification using IDtyperX-16 kit by our independent research followed by capillary electrophoresis. LD was assessed by PowerMarker v3.25 software and mutation rate of every locus was analyzed.@*RESULTS@#LD were not found at the 16 X-STR loci. Allele mutations were observed at 10 loci. Among them, mutation rates of DXS6809 and DXS7132 were both up to 0.0048.@*CONCLUSION@#When the 16 X-STR loci included in IDtyperX-16 kit were used for parentage testing, product princi- ples can be applied to calculate the likelihood, but mutation should be taken into consideration in the case that the genotypes do not meet the genetic law (especially at DXS6809 and DXS7132).

Progress in InDel as a new generation of genetic marker / 法医学杂志

As forensic DNA typing experienced three generations of genetic marker researching stage, short tandem repeat (STR) has been widely used in forensic identification as a mature tool. Further exploration of the human genome led to the discovery of polymorphism markers of single nucleotide polymorphism (SNP) and Insertion/Deletion (InDel). InDel, which combines the desirable characteristics of previous genetic markers as a new type of genetic marker, has got extensive concern in fields like medical molecular biology and forensic biology. This paper generally reviews the history of research and the corresponding results of InDel along the line of time axis as well as the different aims of these research focusing on the progress in the multiple amplification system with several InDel as the genetic marker (autosomal or X chromosome) in forensic biology and anthropology. Finally, the direction of research in this field and the problems to be solved have been put forward.

Forensic application of investigator Argus X-12 kit in Han population from East China / 法医学杂志

OBJECTIVE@#To investigate the genetic data of the 12 X-STR included in Investigator Argus X-12 kit and to evaluate the forensic application in Han population from East China. 9: By detecting 309 unrelated individuals with Investigator Argus X-12 kit, allele frequencies, population genetics parameters and the information of linkage disequilibrium of the 12 X-STR were analyzed by statistics and were compared with available data of other Han populations from different regions.@*RESULTS@#No deviations from Hardy-Weinberg equilibrium were detected. Except loci of DXS10103 and DXS10101 linked closely, all other loci were independent while HET exceed 0.5 and PIC all above 0.4. Distributions of allele frequencies of all loci were not significant statistically except for locus of DXS10146 in Han population from Guangdong.@*CONCLUSION@#Loci of Investigator Argus X-12 kit were highly polymorphic in Han population from East China, which is suitable for forensic application in paternity testing and individual identification.