To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application. 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. 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 （ ）-0.966 9 （ ）. 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）]. The sy
With the development of the computer simulation technology and the digital simulation technology, the traditional calculation method has been gradually replaced by the digital method to deal the road traffic accident scene and analyse the process. The PC-Crash software simulation system can reconstruct the traffic accidents within 32 vehicles, and the accuracy of reconstruction has been fully verified, which is widely used by the transport police department and the accreditation agency. In this paper, the research of road traffic accident reconstruction using PC-Crash software is reviewed, and the application of road traffic accident reconstruction technology based on PC-Crash software and some existing problems in forensic practice are discussed, which provides reference for the research and identification of road traffic accident simulation and reconstruction and theoretical basis for accident treatment.
To develop a measurement software of lung compression degree to calculate the lung compression ratio in pneumothorax patients accurately and quickly, and then provide an objective assessment of damage degree in forensic clinical identification. A volume calculation software was established according to the working principle of the CT instrument. CT data of 15 pneumothorax patients were selected as research objects. The lung compression ratio of pneumothorax patient was calculated by the lung compression volume calculation software of the CT instrument. Meanwhile, the lung compression ratio was also calculated by the developed volume calculation software. The lung compression ratio and operation time calculated by the two methods were analyzed statistically. Scatter plot graphs were draw based on related data, and the developed volume calculation software was verified. The difference between the lung compression ratios calculated by the two methods was not statistically significant, but showed a linear correla
Age estimation is a hot and difficult issue in forensic practice. Teeth are the most solid organs in human body and can be kept in vitro for a long time. With age, the secondary dentin gradually generates and the volume of pulp cavity constantly decreases. Therefore, forensic dentists proposed that age-related changes of dentin-pulp complex could be used to estimate age, which has been widely applied in forensic practice over the years. Due to the development of imaging technology, a variety of methods have been advocated by forensic dentists to detect the age-related changes of dentin-pulp complex for age estimation. However, different methods have their own advantages and limitations, forensic scientists should combine the use of different methods for improving the accuracy of age estimation according to the actual situation. This paper reviews current research of age estimation based on dentin-pulp complex, so as to provide reference for related research.
To study the correlation between the movement distance of small intestinal contents and survival time in female SD rat models after one-time satiation, and to evaluate its application value for postmortem interval estimation. Adult female SD rats were randomly divided into postprandial groups （1, 2, 3, 4 and 5 h after feeding） and control group. The postprandial groups were fed for 1 h, meanwhile control group was kept fasting. All rats were sacrificed at the given time. The contents in stomach and small intestine were observed, described, compared and photographed, and the movement distance of small intestinal contents was measured. The data of postprandial groups were analysed by one-way analysis of variance. The stomach and duodenum of control group were empty with a little thin and yellow small intestinal liquid. The gastral cavities of 1 h postprandial group were full of undigested food. The evolutionary changes of character, colour and content were observed in the gastric and small intestinal contents o
With the continuous development of DNA extraction and testing technology, the DNA left at a crime scene plays a decisive role in the determination of criminal suspects in criminal investigation. But in the meanwhile, the anti-reconnaissance awareness of suspect is growing, which leads to a decrease of evidence left at scene during and after a crime. Therefore, in the process of evidence collection at scene, the finding and extraction of touch biological evidence, and the DNA detection are more and more important. At present, the proportion of touch evidence at the crime scene increases, which plays an increasingly important role in the detection of cases. However, with the characteristics of minute quantities, small size and secrecy, these touch evidence is difficult to be observed. What's more, various forms of pollution at the scene greatly accelerate the degradation rate of trace material, thus, the test and analysis of such material has become the emphasis and difficulty of the forensic evidence identific
Forensic ancestry inference refers to the application of ancestry inference of population genetics in forensic practice, which aims to assist police investigation and judicial trial. With the rapid development and extensive use of genomics, DNA as a direct carrier of genetic information, has soon replaced various phenotypic markers and become the main research topics of forensic ancestry inference. This paper reviews different kinds of genetic markers used for forensic ancestry inference, the statistical analysis methods applied, and the prospects of the development in this field.
To identify the new designer drugs which are totally unknown and not in the routine testing list by the technologies such as high-resolution mass spectrometry in drug facilitated sexual assault, in order to solve the problem in actual cases. The milky fluid from an actual case was extracted and analyzed using LC-QE, ¹H-NMR and GC-MS, respectively. The accurate masses and cluster ions isotope patterns of unknown compound were obtained by LC-QE. The molecular formula was confirmed as C₁₆H₁₂C₂N₂O based on the protons number of ¹H-NMR. The isomers diclazepam and 4-chlorodiazepam were separated and detected with GC-MS. The new designer benzodiazepine as diclazepam in the milky fluid was identified. The results provided direct evidence for the investigation and qualitative analysis of such cases. The combined application of various methods, including LC-QE, ¹H-NMR and GC-MS, can be used to detect unknown new psychoactive substances.
To investigate the genetic polymorphisms of 27 Y-STR in Dongxiang population of Gansu province, and to explore the population genetic relationship and the value of forensic application. The genotyping of 27 Y-STR loci in 526 unrelated male individuals in Dongxiang population of Gansu province were detected by STRtyper-27Y kit. The allele frequencies and haplotype diversity were also calculated. Combining with other genetics data of 14 loci in same populations, which have been published at home and abroad, the genetic distance and clustering relationship in Dongxiang population of Gansu province were calculated. Totally 55 haplotypes were found in the biallelic loci, 39 haplotypes in loci, and 4-16 alleles in the rest 23 single copy STR loci. The GD value was from 0.453 9 （ ） to 0.957 5 （ ）. Totally 471 haplotypes were observed in 27 Y-STR loci in 526 individuals, and the value of haplotypes diversity was 0.999 5. The genetic distance between Dongxiang and Tibetan populations of Gansu province was the closest
To calculate genetic parameters of SNP loci in next generation sequencing kits, and to compare them with STR loci for establishing the conversion ratio between SNP and STR system effectiveness. Hardy-Weinberg equilibrium tests were performed in 101 SNP loci of next generation sequencing kits （ForenSeq™ DNA Signature Prep kit and Precision ID Identity Panel kit）. The parameters of system effectiveness of SNP loci in the cases of personal identification, trios, duos, and alleged parents were calculated, which were compared with the genetic parameters of STR loci. Except 2 loci without the data of genotype frequency, other 99 SNP loci conformed to Hardy-Weinberg equilibrium tests （ >0.05）. In ForenSeq™ DNA Signature Prep kit, the CDP of 94 SNP loci was 1-1.152 1×10⁻³⁴, CPE was 1-4.416 9×10⁻⁸, CPE was 1-8.483 7×10⁻⁵, and CPE was 1-1.222 7×10⁻¹². In Precision ID Identity kit, the CDP was 1-2.052 4×10⁻³³, CPE was 1-8.709 3×10⁻⁸, CPE was 1-1.163 8×10⁻⁴, and CPE was 1-3.725 7×10⁻¹². In the cases of personal identific
To study the urinary metabolic profile in rats with deep venous thrombosis （DVT） based on metabolomics and to screen out small molecular biomarkers for the diagnosis and forensic identification of DVT. Inferior vena cava of rats was ligated to construct DVT models. The rats were randomly divided into three groups： DVT, sham, and control groups, 10 in each group. The urine of DVT and sham rats was collected during 24 hours in the metabolic cage at 48 hours after operating, meanwhile, 24 hours urine was collected in control group. The metabolic profile was analyzed by nuclear magnetic resonance. SIMCA-P 14.1 software was used for pattern recognition. The variable importance in projection （VIP） value from orthogonal PLS-DA （OPLS-DA） model combined with Mann-Whitney test were used to search the different metabolites in the urine. The metabolic profiles of urine from DVT, sham, and control groups had significant differences. The DVT, sham, and control groups could be distinguished by the partial least squares meth
To analyse the Fourier transform infrared （FTIR） spectral data of renal tissue at different temperatures in rats after death, and to explore the effects of temperature on the FTIR spectral characteristics of renal tissue. The rats were sacrificed by cervical dislocation and placed at 4 ℃, 20 ℃ and 30 ℃. The FTIR spectral data of renal tissue were collected at different time points and analysed by data mining method. The principal component analysis （PCA） results showed that there were significant trends of clustering in the samples of partial time point at 4 ℃, 20 ℃ and 30 ℃. Partial least square （PLS） regression models were established with the spectral data at three temperature groups. The performance of PLS regression models in 20 ℃ and 30 ℃ groups were more superior than that in 4 ℃ group, and the stability of the model in 20 ℃ group was better than that in 30 ℃ group. There are differences in the FTIR spectral characteristics of renal tissue of rats after death at different temperatures. Temperature has
To study the injury manners of Bennett fracture and Rolando fracture and explore its identification principle of the first metacarpal base fractures. Totally 31 cases of Bennett fracture and Rolando fracture were collected. The injury manners of cases of 19 Bennett fractures and 12 Rolando fracture were classified, and various injury manners were analysed statistically. The injury manners of the cases of 19 Bennett fracture and 12 Rolando fracture were divided into three types, including the first metacarpus hit hard objects during a punching, the first metacarpus hit hard objects when making fists and fell, or the first metacarpus was punched by hard objects when making fists. The injury mechanism of Bennett fracture and Rolando fracture is formed by a force on the first metacarpus when making fists, which transmits to the basilar part along the vertical axis of metacarpus. The inference of injury manners should be focused on the confirmation of entrusted matters.
To analyse the genetic polymorphisms of 19 autosomal STR loci in Han population of east, middle-northwest and southwest-south Shandong and to explore its genetic relationships among the population of these three regions. STR loci of 1 044 unrelated Han individuals in three Shandong regions were typed with a Golden ye® DNA ID System 20A kit. The allele frequency and population genetics parameters of 19 autosomal STR loci were statistically analysed by Modified-Powerstates software. The genetic distances among the population in three regions were calculated by Arlequin v3.5 software. The phylogenetic tree was conducted using MEGA v4.0 software. Fifteen of 19 autosomal STR loci were detected with the H values greater than 0.7, PIC values greater than 0.7, and DP values greater than 0.9 in the populations of all three Shandong regions. Among the populations in these three regions, the genetic distance between the populations in middle-northwest and southwest-south Shandong was closest （ =0.000 16）, followed by ea
To analyze the relationship between the suicide method and the sex, age, education background and cause of suicide to provide reference for the forensic identification of suicide. After scene investigation, external body examination, autopsy and case investigation, 124 identified suicide cases which happened in recent three years in Wuhua district in Kunming were collected. Analytical methods as chi-square test and descriptive statistics were performed by SPSS 22.0. In all the suicide cases, male to female ratio was 1.53∶1. The suicide methods were mainly fatal fall, hanging and drowning. The ratio of local to non-native residents was 1∶1. The suicide rate in the people with primary school or junior middle school education level was highest. The group of >10-50 years tended to choose fatal fall suicide and people over 60 years were more likely to choose hanging. People with different academic background tended to choose fatal fall suicide. The suicide methods as fatal fall and hanging were chosen because of m
To establish a height prediction model of Chinese Han male based on the reported 547 height-associated single nucleotide polymorphisms （SNPs） loci in Europeans, and assess its accuracy for height estimation. The DNA typing was analyzed in 59 Han male samples of Shandong province by Affymetrix SNP Array 6.0 chip and HiSeq 4000 sequencing platform. Prediction model was established using 547 height-associated SNPs loci as predictors and weight allele sums （WAS） as computing method. The accuracy of height prediction model was analysed using receiver operating characteristic （ROC） curve and area under curve （AUC）. There was no height-associated SNPs locus was found by genome-wide association studies. In present study, height prediction model was established by WAS and obtained an AUC of 0.67 （95% CI: 0.53-0.90）. It has reference value for predicting the height of Han male in Shandong province by WAS model based on 547 SNPs loci, while it is still necessary to further promote the accuracy of the prediction model by
To investigate the genetic polymorphism of 21 autosomal STR loci and locus of SiFaSTR™ 23plex DNA ID system in Han population of eastern China and to evaluate its application value in forensic science. Typing test of 2 000 unrelated individuals was performed using SiFaSTR™ 23plex DNA ID system. The population genetic parameters of STR loci were statistically analysed. A total of 3 198 parentage confirmed cases were detected with that system and the mutation conditions were observed in 21 autosomal STR loci. All the 21 autosomal STR loci showed no significant departure from Hardy-Weinberg equilibrium （ >0.05）. The Ho ranged from 0.617 5 to 0.927 0. The DP ranged from 0.796 4 to 0.986 9, as well as the PIC distributed from 0.561 1 to 0.912 3. The CDP was 0.999 999 999 999 999. The CPE was 0.999 997 431 701 961, while CPE was 0.999 999 999 654 865. Five alleles were detected in locus, with the allele frequency from 0.004 0 to 0.729 0, and GD was 0.418 9. Except and , seventy-six mutation events were observed at
To detect 715 bp sequence of 28S rRNA in sarcosaphagous flies, and to identify their common species for solving the problem of morphological identification, as well as providing technical support for postmortem interval （PMI） estimation. Twenty-nine common sarcosaphagous flies were collected in Luoyang and classified by morphological characteristics. The DNA was extracted from the fly's legs by Chelex-100 method and then the fragments of 28S rRNA were amplified and sequenced. The results were compared with twenty-eight corresponding fly species of GenBank and EMBL databases. All the sequences were analyzed by MEGA7.0 software, and sequence alignment was performed by the searching in BLAST. The nucleotide composition was analysed, and the intraspecific and interspecific genetic distance and phylogenetic tree were established. Twenty-nine sarcosaphagous flies were classified into 6 species of 5 genera, 3 families by morphological characteristics. In the obtained 715 bp sequence of 28S rRNA, the comparison resul
To explore the effect of benzidine test and related reagents on DNA analysis of bloodstain. A total of 970 bloodstain filter paper samples with 1 μL venous blood were collected, and 10 of them acted as control samples. After benzidine test and related reagent processing, DNA of 960 samples was extracted by Chelex-100 and silica bead methods and then multiplex amplified by AmpFℓSTR™ Identifiler™ Plus PCR kits. The results of STR typing were compared between different groups. DNA were extracted immediately after benzidine test. Totally STR loci （3.80±1.34） were detected by silica bead method, while no STR loci were obtained by Chelex-100 method. Thirteen samples （21.7%） with whole STR typing results were obtained by drying after benzidine test, and the STR locus number （12.90±1.49） which obtained by silica bead method was much higher than by Chelex-100 method （4.70±1.96） （ <0.05）. When DNA was extracted immediately after the addition of glacial acetic acid, the STR locus number was （9.40±2.09） by silica bead me
To establish a method for the age estimation of adult living donor based on pubic MSCT three-dimensional reconstruction and verify its accuracy and reliability. The volume rendering （VR） image data of pubic symphysis surface were collected from 300 volunteers aged over 17 years old. According to different age groups, the age estimation of these volunteers was performed by the method and formula of pubic symphysis surface. In the 300 volunteers, the difference between biological age and actual age was 1-2 years in 178 cases, >2 years in 5 cases. MSCT three-dimensional reconstruction technology of pubic symphysis surface can be used to estimate the age of adult living donor, which can provide a high accurate and reliable result.