[Genetic Polymorphisms of 27 Y-STR Loci in Dongxiang Population of Gansu Province].

OBJECTIVES: 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. METHODS: 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. RESULTS: Totally 55 haplotypes were found in the DYS385a/b biallelic loci, 39 haplotypes in DYF387S1 loci, and 4-16 alleles in the rest 23 single copy STR loci. The GD value was from 0.453 9 （DYS391） to 0.957 5 （DYS385a/b）. 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 （0.068 2）, while it was the longest between Dongxiang population in Gansu province and Han population in Henan province （0.084 7）. The result of dimensional analysis established upon the genetic distance was basically matched with that of the cluster analysis. CONCLUSIONS: The 27 Y-STR loci show a high genetic polymorphism in Dongxiang population of Gansu province, which has significance for the Y-STR database establishment, population genetics study and forensic practice.

Genetic Polymorphisms of 18 Autosomal STR loci in Changsha Han Population.

OBJECTIVES: To investigate the genetic polymorphisms of 18 autosomal short tandem repeats （STR） loci in Changsha Han population, and explore the population genetic relationships and evaluate its application value in forensic medicine. METHODS: The DNA of 2 004 unrelated individuals in Changsha Han population were amplified using Goldeneye®DNA ID System BASIC, and the PCR products were analyzed by electrophoresis using 3130xl genetic analyzer. The fragment sizes of alleles were analyzed subsequently by GeneMapper® ID v3.2. The frequency data and forensic genetic parameters ï¼»observed heterozygosity （Ho）, expected heterozygosity （He）, power of discrimination （DP） and polymorphic information content （PIC）］ of 18 STR loci were statistically analyzed. Total probability of discrimination （TDP）, probability of exclusion in trio cases （PEtrio） and probability of exclusion in duo cases （PEduo） were calculated by Cervus 3.0. Hardy-Weinberg equilibrium and linkage disequilibrium of the loci were detected by Arlequin v3.5. The results were compared with the available data of other populations from different races and regions. RESULTS: The power of discrimination （DP）, and the polymorphic information content （PIC） of each locus of Changsha Han population ranged from 0.783 6 to 0.987 9 and 0.549 4 to 0.914 5, respectively. The TDP, cumulative probability of exclusion in trio cases （CPEtrio） and cumulative probability of exclusion in duo cases （CPEduo） were 0.999 999 999 999 999 999 999 865 2, 0.999 999 979 and 0.999 988 325, respectively. According to the Nei's DA genetic distance, the genetic distance between Changsha Han and Hunan Han populations was the smallest （0.014 1）, while it was the largest （0.041 8） between Changsha Han and Xinjiang Kazakh populations. CONCLUSIONS: The 18 STR loci shows abundant genetic polymorphisms in Changsha Han population. The study of genetic diversity among different populations has an important meaning for the research of their origins, migrations and their relationships.

[Identification of Y-chromosomal Genetic Types for the Soldier's Remains from Huaihai Campaign].

OBJECTIVES: To identify the Y-chromosomal genetic types for the soldier's remains from Huaihai Campaign, and to offer a clue for search of their paternal relatives. METHODS: DNA of the remains were extracted by the ancient DNA extraction method. Yfiler kit was used for the multiplex amplification of 17 Y-STR loci. The haplogroups of the samples were speculated. Detailed genotyping of the selected Y-SNP was performed based on the latest Y-chromosome phylogenetic tree. Haplotype-sharing analysis was done based on the data of Y-SNP and Y-STR, the closest modern individual information to the genetic relationship of remains was gained. RESULTS: A total of 8 Y-STR haplotypes were observed on 17 Y-STR loci of 8 male individuals. Furthermore, 6 Y-SNP haplogroups were identified, which were O2a1-M95+, O1a1-P203+, O3*-M122+/M234-, D1-M15+, C3*-ST and R1a1-M17+. CONCLUSIONS: Identification of Y-chromosomal genetic types for the soldier's remains from Huaihai Campaign shows a reference value on inferring the geographical origins of old materials.

[Forensic Application of 16 X-STR Loci in Henan Han Population].

OBJECTIVES: To investigate the genetic data of 16 X-STR loci in Henan Han population and to assess the application value in forensic science. METHODS: The DNA of 326 unrelated individuals in Henan Han population were amplified using Goldeneye™ DNA identification system 17X kit, and the PCR products were analyzed by electrophoresis through 3130xl genetic analyzer. The fragment sizes of alleles were analyzed subsequently by GeneMapper® ID-X. Allele frequencies and population genetics parameters of 16 X-STR loci were analyzed statistically and compared with the available data of other Han populations from different regions. RESULTS: Among the 16 X-STR loci, DXS6800 were found to be moderately polymorphic and the other 15 X-STR loci were highly polymorphic. The cumulative discrimination power in females and males were 0.999 999 999 999 992 and 0.999 999 996 577 712, respectively. The combined power of exclusion in trios and in duos were 0.999 999 971 and 0.999 992 574, respectively. CONCLUSIONS: The 16 X-STR loci meet the application requires of forensic genetics, especially for testing the special paternity cases.