Humans ; Urinary Bladder Neoplasms/pathology* ; Carcinoma, Transitional Cell/pathology* ; Genetic Markers ; Biomarkers, Tumor/genetics* ; Urothelium/pathology*

OBJECTIVES: To compare the application value of the likelihood ratio (LR) method and identity by state (IBS) method in the identification involving half sibling relationships, and to provide a reference for the setting of relevant standards for identification of half sibling relationship. METHODS: (1) Based on the same genetic marker combinations, the reliability of computer simulation method was verified by comparing the distributions of cumulated identity by state score (CIBS) and combined full sibling index in actual cases with the distributions in simulated cases. (2) In different numbers of three genetic marker combinations, the simulation of full sibling, half sibling and unrelated individual pairs, each 1 million pairs, was obtained; the CIBS, as well as the corresponding types of cumulative LR parameters, were calculated. (3) The application value of LR method was compared with that of IBS method, by comparing the best system efficiency provided by LR method and IBS method when genetic markers in different amounts and of different types and accuracy were applied to distinguish the above three relational individual pairs. (4) According to the existing simulation data, the minimum number of genetic markers required to distinguish half siblings from the other two relationships using different types of genetic markers was estimated by curve fitting. RESULTS: (1) After the rank sum test, under the premise that the real relationship and the genetic marker combination tested were the same, there was no significant difference between the simulation method and the results obtained in the actual case. (2) In most cases, under the same conditions, the system effectiveness obtained by LR method was greater than that by IBS method. (3) According to the existing data, the number of genetic markers required for full-half siblings and half sibling identification could be obtained by curve fitting when the system effectiveness reached 0.95 or 0.99. CONCLUSIONS When distinguishing half sibling from full sibling pairs or unrelated pairs, it is recommended to give preference to the LR method, and estimate the required number of markers according to the identification types and the population data, to ensure the identification effect.
Humans ; Siblings ; Genetic Markers ; Computer Simulation ; Irritable Bowel Syndrome/genetics* ; Reproducibility of Results ; Genotype

OBJECTIVES: To explore the feasibility of genetic marker detection of semen-specific coding region single nucleotide polymorphism (cSNP) based on SNaPshot technology in semen stains and mixed body fluid identification. METHODS: Genomic DNA (gDNA) and total RNA were extracted from 16 semen stains and 11 mixtures composed of semen and venous blood, and the total RNA was reverse transcribed into complementary DNA (cDNA). The cSNP genetic markers were screened on the validated semen-specific mRNA coding genes. The cSNP multiplex detection system based on SNaPshot technology was established, and samples were genotyped by capillary electrophoresis (CE). RESULTS: A multiplex detection system containing 5 semen-specific cSNPs was successfully established. In 16 semen samples, except the cSNP located in the TGM4 gene showed allele loss in cDNA detection results, the gDNA and cDNA typing results of other cSNPs were highly consistent. When detecting semen-venous blood mixtures, the results of cSNP typing detected were consistent with the genotype of semen donor and were not interfered by the genotype of venous blood donor. CONCLUSIONS The method of semen-specific cSNPs detection by SNaPshot technology method can be applied to the genotyping of semen (stains) and provide information for determining the origin of semen in mixed body fluids (stains).
Genetic Markers ; Semen ; Polymorphism, Single Nucleotide ; DNA, Complementary/genetics* ; Body Fluids ; RNA, Messenger/genetics* ; DNA ; Saliva ; Forensic Genetics/methods*

In recent years, more and more forensic genetics laboratories have begun to apply massively parallel sequencing (MPS) technology, that is, next-generation sequencing (NGS) technology, to detect common forensic genetic markers, including short tandem repeat (STR), single nucleotide polymorphism (SNP), the control region or whole genome of mitochondrial DNA (mtDNA), as well as messenger RNA (mRNA), etc., for forensic practice, such as individual identification, kinship analysis, ancestry inference and body fluid identification. As the most widely used genetic marker in forensic genetics, STR is currently mainly detected by capillary electrophoresis (CE) platform. Compared with CE platform, MPS technology has the advantages of simultaneous detection of a large number of genetic markers, massively parallel detection of samples, the polymorphism of sequence detected by NGS makes STR have the advantages of higher resolution and system efficiency. However, MPS technology is expensive, there is no uniform standard so far, and there are problems such as how to integrate MPS-STR data with the existing CE-STR database. This review summarizes the current status of the application of MPS technology in the detection of STR genetic markers in forensic genetics, puts forward the main problems that need to be solved urgently, and prospects the application prospect of this technology in forensic genetics.
DNA Fingerprinting/methods* ; Forensic Genetics/methods* ; Genetic Markers ; High-Throughput Nucleotide Sequencing/methods* ; Microsatellite Repeats/genetics* ; Polymorphism, Single Nucleotide ; Sequence Analysis, DNA ; Technology

Humans ; Genetic Markers ; Family ; DNA Fingerprinting ; Microsatellite Repeats/genetics*

Genetic factors play a key role in human athletic ability, and endurance quality and explosive power quality are the important components of athletic ability. In this review, we aimed to reveal the biological genetic mechanism of human athletic ability at the molecular level through summarizing the relationship between genetic variants and human athletic ability, including endurance quality related genetic markers angiotensin converting enzyme (ACE) gene, creatine kinase MM (CKMM) gene and explosive power quality related genetic markers alpha actinin 3 (ACTN3) gene, angiotensinogen (AGT) gene and interleukin6 (IL6) gene. Meanwhile, we also summarized the distribution of allele frequencies among various populations.
Actinin/genetics* ; Athletic Performance ; Gene Frequency ; Genetic Markers ; Genotype ; Humans ; Polymorphism, Genetic

OBJECTIVES: To identify whether the relationship between Zhang A, Zhang B, Zhang C and Zhang X is the half-sibling relationship whose mother is sister (hereinafter referred to as the special half-sibling relationship) or the common first cousin relationship and discuss the application of ITO method in discriminating the special kinship. METHODS: DNA was extracted from blood stain of four identified individuals, PowerPlex^® 21 System and AGCU 21+1 STR kit were used to detect autosomal STR genetic markers. Investigator^® Argus X-12 QS kit was used to detect the X chromosome STR genetic markers, the special half-sibling index (SHSI) and first cousin index (FCI) and their likelihood ratio (LR) were calculated by ITO method. RESULTS: The LR results of SHSI to FCI, which were calculated based on autosomal STR genotyping and the analysis of X-STR genotyping results suggested that the relationship between Zhang A, Zhang B, Zhang C and Zhang X was inclined to be a special half-sibling relationship. CONCLUSIONS For the identification of special kinship, it is necessary to comprehensively apply various genetic markers according to the case. After the conclusion that shared alleles cannot be excluded from the analysis, ITO method can be further used to establish discriminant assumptions according to the specific case to obtain objective and reliable identification opinions.
Alleles ; DNA Fingerprinting ; Family ; Genetic Markers ; Genotype ; Humans ; Microsatellite Repeats ; Siblings

The paternal inheritance characteristics of Y chromosome have been widely used in the forensic genetics field to detect the genetic markers in the non-recombining block, and used in the studies such as, genetic relationship identification, mixed stain detection, pedigree screen and ethnicity determination. At present, capillary electrophoresis is still the most common detection technology. The commercial detection kits and data analysis and processing system based on this technology are very mature. However, the disadvantages of traditional detection technology have gradually appeared with the rapid growth of bio-information amount, which promotes the renewal of forensic DNA typing technology. In recent years, next generation sequencing （NGS） technology has developed rapidly. This technology has been applied to various fields including forensic genetics and has provided new techniques for the detection of Y chromosome genetic markers. This article describes the current situation and application prospects of the NGS technology in forensic Y chromosome genetic markers detection in order to provide new ideas for future judicial practice.
Chromosomes, Human, Y/genetics* ; DNA Fingerprinting ; Forensic Genetics ; Genetic Markers ; High-Throughput Nucleotide Sequencing ; Humans ; Microsatellite Repeats ; Technology ; Y Chromosome

Objective To assess the feasibility of the rbcL sequence of chloroplast DNA as a genetic marker to identify Cannabis sativa L. Methods The rbcL sequences in 62 Cannabis sativa L. samples, 10 Humulus lupulus samples and 10 Humulus scandens DNA samples were detected, and 96 rbcL sequences of the Cannabaceae family were downloaded from Genbank. Sequence alignment was performed by MEGA X software, the intraspecific and interspecific Kimura-2-Parameter （K2P） genetic distances were calculated, and the system clustering tree was constructed. Results The rbcL sequence length acquired by sequencing of Cannabis sativa L. and Humulus scandens were 617 bp and 649 bp, respectively, and two haplotypes of Cannabis sativa L. were observed in the samples. The BLAST similarity search results showed that the highest similarity between the sequences acquired by sequencing and Cannabis sativa L. rbcL sequences available from Genbank was 100%. The genetic distance analysis showed that the maximum intraspecific genetic distance （0.004 9） of Cannabis sativa L. was less than the minimum interspecific genetic distance （0.012 9）. The results of median-joining network and system clustering tree analysis showed that Cannabis sativa L. and other members of the Cannabaceae family were located in different branches. Conclusion The rbcL sequence could be used as a DNA barcode for identifying Cannabis sativa L., and combined with comparative analysis of the rbcL sequence and system cluster analysis could be a reliable and effective detection method for Cannabis sativa L. identification in forensic investigation.
Cannabis/genetics* ; Genetic Markers ; Sequence Analysis, DNA

Objective To derive the probability distribution formula of combined identity by state （CIBS） score among individuals with different relationships based on population data of autosomal multiallelic genetic markers. Methods The probabilities of different identity by state （IBS） scores occurring at a single locus between two individuals with different relationships were derived based on the principle of ITO method. Then the distribution probability formula of CIBS score between two individuals with different relationships when a certain number of genetic markers were used for relationship identification was derived based on the multinomial distribution theory. The formula was compared with the CIBS probability distribution formula based on binomial distribution theory. Results Between individuals with a certain relationship, labelled as RS, the probabilities of IBS=2, 1 and 0 occurring at a certain autosomal genetic marker x （that is, p_2（RSx）, p_1（RSx） and p_0（RSx））, can be calculated based on the allele frequency data of that genetic marker and the probability of two individuals with the corresponding RS relationship sharing 0, 1 or 2 identity by descent （IBD） alleles （that is, φ₀, φ₁ and φ₂）. For a genotyping system with multiple independent genetic markers, the distribution of CIBS score between pairs of individuals with relationships other than parent-child can be deducted using the averages of the 3 probabilities of all genetic markers （that is, p_2（RS）, p_1（RS） and p_0（RS））, based on multinomial distribution theory. Conclusion The calculation of CIBS score distribution formula can be extended to all kinships and has great application value in case interpretation and system effectiveness evaluation. In most situations, the results based on binomial distribution formula are similar to those based on the formula derived in this study, thus, there is little difference between the two methods in actual work.
Alleles ; Gene Frequency ; Genetic Markers ; Genotype ; Humans ; Probability