Genetic polymorphisms for 19 autosomal STR loci of Chongqing Han ethnicity and phylogenetic structure exploration among 28 Chinese populations

A Tibetan group from Ngawa Tibetan and Qiang Autonomous Prefecture, southwest China, is rich in genetic polymorphisms at 36 autosomal STR loci and shares a complex genetic structure with other Chinese populations

The Tibetan people are ancient and populous, constituting the seventh-largest of the fifty-five ethnic minority groups in China. The Ngawa Tibetan and Qiang Autonomous Prefecture (NTQAP), situated on the border of northwest and southwest China, has its distinct group relationships. Short tandem repeat (STR) is extremely polymorphic and extensively used in the application of forensic medicine and population genetics. However, it is not clear the genetic information including linkage disequilibrium (LD) by 36 autosomal STR (A-STR) markers in the Tibetan group from NTQAP. The Tibetan population from NTQAP of southwest China was examined for 36 A-STR loci in the research. Every marker across the 36 A-STR loci was consistent with Hardy-Weinberg equilibrium (HWE). The results of the calculation revealed that the total discrimination power (TDP) is 1-2.2552 × 10-42 and the cumulative probability of exclusion (CPE) is 1-1.3031 × 10-16. Subsequently, a total of 345 alleles with allelic frequencies ranging from 0.00382 to 0.55343 were identified, and the allelic numbers varied from 5 in both the TH01 and TPOX markers to 28 in the SE33 locus. The Ngawa Tibetan population, along with other Chinese populations, exhibited influences from historical factors and regional distribution, as indicated by the results of population genetics analysis. We thus first explored the genetic characteristics and correlated forensic parameters of the 36 A-STR markers in NTQAP to fill the gap in the Tibetan population. It was discovered that these 36 autosomal STR markers supplemented forensic STR databases and offered extremely valuable polymorphisms for Chinese forensic applications, such as parentage testing and personal identification. Moreover, the study would contribute additional information regarding the substructure and diversity in the Chinese population.

Genetic Polymorphism and Population Genetic Structure Analysis of 21 Autosomal STR Loci for a Han-Chinese Population from Luzhou of Southwest China

The Han nationality is an ancient and populous people, and different places in China may have their distinct group relationships. Luzhou area, as a crossroads of several provinces in Southwest China, lacks autosomal short tandem repeat (STR) research and population genetics research. In this study, 21 autosomal STR loci were evaluated in 1959 Han-Chinese individuals from Luzhou area. There was no substantial linkage disequilibrium (LD) among the 21 autosomal STR markers, and all markers were in Hardy-Weinberg equilibrium (HWE). The total discrimination power (TDP) and cumulative probability of exclusion (CPE) of the 21 autosomal STR loci were calculated to be 1-9.8505 × 10^-16 and 1-1.9406 × 10^-9, respectively. There were 333 alleles for 21 STRs with allelic frequencies ranging from 0.00026 to 0.51302, and the number of alleles ranged from 7 in locus TPOX to 29 in locus Penta E. According to the results of population comparison and population differentiation, historical influences, geographical distribution, cultural integration, and economic development may have an impact on the Luzhou Han population and other Chinese populations. These 21 STR loci were found to enrich autosomal STR information in forensic databases and provide highly informative polymorphisms for our forensic practice in China, including personal identification and parentage testing.

FST estimates of 94 populations in China based on STR markers

The proper assessment of DNA evidence in cases of personal identification is a recurring theme in forensics. It is common practice to evaluate the strength of DNA evidence using the likelihood ratio (LR). The accurate use of population allele frequencies is a crucial problem in LR calculation. Allele frequency differences among different populations could be estimated by the F_ST values. Thus, F_ST would also affect LR values by correcting the allele frequencies. In this study, Chinese population allele frequency data were selected from population reports published in Chinese and English journals. The population-specific F_ST values of each population, the overall F_ST values of each province, each region, and the whole country, and the locus-specific F_ST values of different loci were calculated. The LRs using different allele frequencies and different F_ST values were compared based on the combination of simulated genotypes. As a result, the F_ST values of 94 populations, 19 provinces, 7 regions, and the whole country were obtained. The LR was overestimated using allele frequencies of the combined population containing multiple populations rather than using allele frequencies of a population, and the LRs after F_ST correction were lower than those without correction. Conclusively, the correction in conjunction with corresponding F_ST values can make the LRs more accurate and reasonable.

Genetic diversity of 15 STR loci in Yunnan Va ethnic minority and the phylogenetic relationships with 26 other populations

BACKGROUND

The Va (also called "Wa") people are an ethnic minority living mainly in the southwest of Yunnan Province.

AIM

This study was conducted to obtain the genetic information and forensic statistical parameters of 15 autosomal short tandem repeat (STR) loci included in the AmpFlSTR^®Identifiler™ kit (Applied Biosystems, Foster City, CA) in the Yunnan Va population, with a view to enriching the genetic databases of the Chinese Va population.

SUBJECTS AND METHODS

A total of 508 unrelated Chinese Va individuals were genotyped with this 15 STR kit, the genetic polymorphisms and associated forensic parameters were calculated. The genetic relationships between Chinese Va and 26 other Chinese populations were also evaluated.

RESULTS

All of the STR loci reached the Hardy-Weinberg equilibrium after Bonferroni correction. A total of 159 alleles were observed with allele frequencies ranging from 0.000984 to 0.606299. The combined discrimination power (CDP) and the cumulative probability of excluding (CPE) of the 15 STR loci were 0.999 999 999 999 999 988 126 and 0.999 995 734, respectively. Our results indicated that the geographically adjacent or ethnically close populations showed a higher genetic affinity.

CONCLUSIONS

The results of this study will enrich the forensic databases of the Chinese Va population and could be applied in forensic analysis.

Genetic polymorphism of 19 autosomal STR loci in the Yi ethnic minority of Liangshan Yi autonomous prefecture from Sichuan province in China

The Yi is one of fifty-six ethnic populations and one of the most ancient ethnic groups in China. The Liangshan Yi Autonomous Prefecture (LYAP) in Sichuan Province has the single largest Yi community in China. To establish a Yi population database in the LYAP of Sichuan in China, a Goldeneye™ DNA Identification System 20A Kit with 19 autosomal STRs (short tandem repeats) was used. As a result, the total discrimination power (TDP) and the cumulative probability of exclusion (CPE) for these STRs in 1016 unrelated individuals were 0.999999999999999999999897 and 0.9999999597, respectively. Totals of 273 alleles for 19 STRs and 8-22 alleles for each locus were found. The allelic frequencies ranged from 0.0005 to 0.5084. The forensic parameter averages of these STRs were as follows: observed heterozygosity (H_obs) of 78.44%, expected heterozygosity (H_exp) of 79.89%, discrimination power (DP) of 92.66%, and probability of exclusion (PE) of 57.68%. Penta E presented the highest levels of H_obs and DP, whereas TPOX showed the lowest H_obs and DP values. Nei's standard genetic distance matrix among 31 populations found that the nearest genetic distance to the Yi population was the Sichuan Han (0.0056). Altogether, we first reported the forensic parameters and allele frequencies of 19 autosomal STRs of the Yi group in Liangshan. These 19 STR makers could provide highly informative polymorphisms for individual identification, paternity testing and genetic population analyses.

Genetic diversity, forensic characteristics and phylogenetic analysis of the Qiongzhong aborigines residing in the tropical rainforests of Hainan Island via 19 autosomal STRs

BACKGROUND

The genetic landscape of the Qiongzhong aborigines, who reside in "the Heart of Hainan," is still unclear. The Goldeneye™ DNA ID System 20 A is available for forensic and population genetics applications.

AIM

To obtain genetic polymorphisms of 19 autosomal STR loci in the Qiongzhong aborigines, and to explore the genetic relationships with a total of 69,132 people from forty-five populations.

SUBJECTS AND METHODS

Genotype data on 19 autosomal STRs were collected from 724 Qiongzhong aborigines and phylogenetic relationships were conducted by multidimensional scaling analysis (MDS), principal component analysis (PCA) and neighbor-joining (N-J) phylogenetic tree construction.

RESULTS

No evidence of deviation from Hardy-Weinberg equilibrium was identified. A total of 233 distinct alleles were observed with allele frequencies ranging from 0.0007 to 0.5375. The combined power of discrimination (CPD) and combined power of exclusion (CPE) for the 19 autosomal STR loci were 1-8.28 × 10^-34 and 0.999999987, respectively.

CONCLUSION

Our phylogenetic results demonstrated that (a) the populations of Southeast Asian countries have thorough integrations with southern China in terms of ethnicity and genetics due to long-term cultural and trade exchanges, and (b) based on genetic and linguistic analysis, the Qiongzhong aborigines have a close relationship with Fujian Han Chinese.HighlightsThe STR landscape of Qiongzhong aborigines inhabited in Hainan tropical rainforests was depicted by 19 autosomal STRs.A total of 69,132 people from forty-five populations were selected for a more extensive examination of genetic similarities and differences by multivariate statistical methods (MDS, PCA and N-J tree construction).The genetic analyses indicated that the populations of Southeast Asian countries are very genetically close to southern Chinese populations.From the genetic and linguistic perspective, the Qiongzhong aborigines have a close relationship with Han Chinese from Fujian Province.

Genetic variation of 20 autosomal STR loci in the Han nationality in Central Yunnan, Southwest China

A total of 20 autosomal short tandem repeat (STR) loci from 2220 unrelated healthy individuals of Han population living in the central area of Yunnan province, Southwest China were amplified with the PowerPlex® 21 System. After Hardy-Weinberg equilibrium examination, the allele frequencies and forensic statistical parameters of 20 STR loci were evaluated. A total of 298 alleles and 1225 genotypes were observed for all the 20 loci. The allele frequencies varied from 0.0002 to 0.5130. The combined power of discrimination and the combined probability of exclusion of all 20 STR loci were 0.99999999521565 and 0.999999999999999999999999637, respectively. Meanwhile, genetic distances between Central Yunnan Han and 17 previously published populations were compared and a neighbor-joining (NJ) phylogenetic tree was developed and visualized by using MEGA 7 based on Nei's standard genetic distance. The results demonstrated that these loci were highly polymorphic in the Han nationality in Central Yunnan, Southwest China and could be applied in forensic medicine and population genetics.

Forensic characteristics and phylogenetic analyses of one branch of Tai-Kadai language-speaking Hainan Hlai (Ha Hlai) via 23 autosomal STRs included in the Huaxia™ Platinum System

BACKGROUND

Hainan Island, located in the South China Sea and separated from the Leizhou Peninsula by Qiongzhou Strait, is the second largest island after Taiwan in China. With the expansion of Han Chinese and the gradual formation of "South Hlai and North Han", nowadays, Hainan Hlai is the second largest population after Han Chinese in Hainan Island. Ha Hlai, distributed in southwest and southern Hainan Island, is the dominant branch of Hlai and speaks Ha localism.

METHODS

We utilized the Huaxia™ Platinum PCR Amplification System (including 23 autosomal STRs and 2 sex-linked markers) to obtain the first STR profiling batch of 657 Ha Hlai individuals (497 males and 160 females). In order to explore the genetic relationships between the studied Ha Hlai and other reference populations with different language families, population genetic analyses, including PCA, MDS, STRUCTURE, and phylogenetic analysis, were conducted based upon the raw data and allelic frequencies of the polymorphic autosomal STR markers.

RESULTS

In total, 271 distinct alleles were observed at the 23 STR loci. The number of diverse alleles ranged from 7 at TPOX locus to 23 at FGA locus, and the allelic frequencies varied from 0.0008 to 0.5533. In addition, the CPE and CPD were 1-7.39 × 10-10 and 1-3.13 × 10-28 , respectively. The phylogenetic analyses indicated that Ha Hlai is a Tai-Kadai language-speaking and relatively isolated population which has a close genetic and geographical relationship with Hainan Hlai, and M95 is the dominant haplogroup in Ha Hlai (56.18%).

CONCLUSION

The 23 autosomal STR genetic markers were highly polymorphic as well as potentially useful for forensic applications in Hainan Ha Hlai population. The phylogenetic analyses demonstrated that small geographic scale gene flows could not be ignored and the shaping of the unique gene pool for each population was the combination effects of geographic, language, and cultural isolations.

Population Genetic Analysis of Modern and Ancient DNA Variations Yields New Insights Into the Formation, Genetic Structure, and Phylogenetic Relationship of Northern Han Chinese

Modern East Asians derived from the admixture of aborigines and incoming farmers expanding from Yellow and Yangtze River Basins. Distinct genetic differentiation and subsequent admixture between Northeast Asians and Southeast Asians subsequently evidenced by the mitochondrial DNA, Y-chromosomal variations, and autosomal SNPs. Recently, population geneticists have paid more attention to the genetic polymorphisms and background of southern-Han Chinese and southern native populations. The genetic legacy of northern-Han remains uncharacterized. Thus, we performed this comprehensive population genetic analyses of modern and ancient genetic variations aiming to yield new insight into the formation of modern Han, and the genetic ancestry and phylogenetic relationship of the northern-Han Chinese population. We first genotyped 25 forensic associated markers in 3,089 northern-Han Chinese individuals using the new-generation of the Huaxia Platinum System. And then we performed the first meta-analysis focused on the genetic affinity between Asian Neolithic∼Iron Age ancients and modern northern-Han Chinese by combining mitochondrial variations in 417 ancient individuals from 13 different archeological sites and 812 modern individuals, as well as Y-chromosomal variations in 114 ancient individuals from 12 Neolithic∼Iron Age sites and 2,810 modern subjects. We finally genotyped 643,897 genome-wide nucleotide polymorphisms (SNPs) in 20 Shanxi Han individuals and combined with 1,927 modern humans and 40 Eurasian ancient genomes to explore the genetic structure and admixture of northern-Han Chinese. We addressed genetic legacy, population structure and phylogenetic relationship of northern-Han Chinese via various analyses. Our population genetic results from five different reference datasets indicated that Shanxi Han shares a closer phylogenetic relationship with northern-neighbors and southern ethnically close groups than with Uyghur and Tibetan. Genome-wide variations revealed that modern northern-Han derived their ancestry from Yakut-related population (25.2%) and She-related population (74.8%). Summarily, the genetic mixing that led to the emergence of a Han Chinese ethnicity occurred at a very early period, probably in Neolithic times, and this mixing involved an ancient Tibeto-Burman population and a local pre-Sinitic population, which may have been linguistically Altaic.

Genetic diversity and forensic characteristics of 15 autosomal short tandem repeats in Tibet highland and Guangdong lowland Han Chinese populations

Background: Much attention has been paid to the genetic variants of microsatellites in East Asian populations; however, genetic diversity of high-altitude adaptation in Tibet Han remains largely uncharacterised. Aim: To profile DNA samples from 338 high-altitude adaptation Han Chinese individuals and 933 low-altitude living Han Chinese individuals for 15 autosomal STRs which are used for human identification purposes and to estimate the forensic parameters as well as explore the genetic relationships among 38 Chinese populations. Subjects and methods: Fifteen autosomal STR loci and amelogenin genes were amplified in 1271 individuals using the AmpFℓSTR^® Sinofiler™ PCR Amplification Kit. Allele frequencies and forensic parameters were calculated. Subsequently, population comparisons among 38 groups were analysed via principal components analysis, Reynolds genetic distance, neighbour-joining tree and multidimensional scaling plots. Results: In this study, no departures from Hardy-Weinberg equilibrium are identified in either Tibet or Guangdong Han populations after Bonferroni correction. The cumulative match probabilities are 3.1108 × 10^-19 in Guangdong Han and 6.2102 × 10^-19 in Tibet Han, and the combined probabilities of exclusion for trios are 0.99999948 and 0.99999936, respectively. Comprehensive population comparisons based on allele frequency distribution indicate that the Tibet Han population has a genetically close relationship with the surrounding population (Tibet Tibetan) and the Guangdong Han population has genetic affinity with southern Chinese populations. Conclusion: In general, genetic polymorphisms and forensic efficiency indicated that the 15 STRs studied are informative and polymorphic in both lowland and highland Han populations.

Forensic characteristics and phylogenetic structure of Eastern Chinese Han populations residing along the Yangtze Basin revealed by 19 autosomal STR loci

In present study, forensic parameters based on the population data of nineteen autosomal short tandem repeats (STRs) loci were estimated in Chinese Han populations from three riverfront areas of Yangtze Basin in Eastern China. The combined power of discrimination (CPD) were 0.9999999999999999999999883, 0.9999999999999999999999846 and 0.9999999999999999999999863, respectively. The combined power of exclusion (CPE) were 0.999999992248957, 0.999999989800400 and 0.999999989799819, respectively. Furthermore, the genetic relationships among our studied populations and 32 previously investigated populations residing in other areas of China were also analyzed based on pairwise genetic distances (F_ST). The multidimensional scaling (MDS) plot and phylogenetic tree indicated that our studied populations were majorly clustered with the Han populations along the Yangtze Basin and populations to the north of it. In summary, our results supported that the 19 autosomal STR loci, which were polymorphic and informative in forensic identification, could also be applied in population genetics studies.

Genetic characteristics and phylogenetic analysis of three Chinese ethnic groups using the Huaxia Platinum System

Short tandem repeats (STRs) are attractive to genetic applications like forensic, anthropological and population genetics studies. The Huaxia Platinum System was specifically developed to allow co-amplification and detection of all markers in the expanded CODIS core loci and the Chinese National Database. In this study, in continuation to our previous validation study, 568 unrelated individuals were firstly genotyped to investigate the effectiveness of this novel assay in 3 main ethnic groups of China (Han, Tibetan and Yi). The combined power of discrimination (CPD) were 0.9999999999999999999999999992, 0.999999999999999999999999992, 0.999999999999999999999999998, respectively, and the combined power of exclusion (CPE) were 0.9999999999, 0.999999995, 0.999999998, respectively. Next, genetic relationships along administrative and ethnic divisions were analyzed using pairwise genetic distances, multidimensional scaling (MDS), principal component analysis (PCA) and phylogenetic analysis. The Han ethnicity showed a high genetic homogeneity all across China, and significant genetic differences existed between Han groups and some minority groups, most prominently for the Tibetans, the Uyghurs, the Kazakhs, the Miaos, the Zhuangs and the Dais. Aforementioned results suggested that the Huaxia Platinum System is polymorphic and informative, which provides an efficient tool not only for human forensics, but also for population genetics studies.

Genetic Diversity and Phylogenetic Differentiation of Southwestern Chinese Han: a comprehensive and comparative analysis on 21 non-CODIS STRs

Short tandem repeats (STRs), with high polymorphism and complex evolution information, play a significant role in genetic association studies like population genetics, molecular anthropology and human forensics. However, human genetic diversity has only been partially sampled and available for Southwest Chinese Han population, as well as the genetic architecture of this population remains uncharacterized. In this work, 368 unrelated Han individuals from Sichuan province were firstly genotyped with 21 non-CODIS autosomal STRs, and phylogenetic relationships along administrative (Han Chinese from different regions) and ethnic divisions (minority ethnic groups) were subsequently investigated. The CMP and CPE were 6.2796 × 10-20 and 0.9999999, respectively. Analysis of molecular variance (AMOVA), principal component analysis (PCA), multidimensional scaling plots (MDS) and phylogenetic analysis consistently demonstrated that the Southwest Han population had a close genetic relationship with the geographically close population (Hunan Han) and kept a distant genetic relationship with some ethnic groups, most prominently for Gansu Yugu and Fujian She. Furthermore, no significant genetic distinction between the Northern Han and Southern Han was observed. Aforementioned results suggested that these 21 STRs are highly polymorphic and informative, which are suitable for human identification and population genetics.

Forensic features and phylogenetic analyses of Sichuan Han population via 23 autosomal STR loci included in the Huaxia Platinum System

Short tandem repeats (STRs) are DNA regions with a variable number of repeated units (2-6 bp) and attractive to genetic application like forensic, population genetics, and anthropological studies. The Huaxia Platinum System allows the multiplex amplification of 23 autosomal STR loci and two gender determination loci. In the present study, genetic polymorphisms of these 23 autosomal STR loci were first obtained from 309 Sichuan Han individuals, southwest China. No evidence of deviation from the Hardy-Weinberg equilibrium (HWE) was identified. The combined match probability (CMP), combined power of discrimination (CPD), and combined power of exclusion (CPE) are 1.087 × 10^-27, 0.999999999999999999999999999, and 0.9999999996 in the Sichuan Han Chinese population, respectively. The inter-population differentiation, PCA, MDS, and phylogenetic analysis revealed that Sichuan Han had a closer genetic relationship with neighboring Han Chinese populations. Our findings indicated that the 23 autosomal STR loci are polymorphic and informative in studied southwestern Chinese Han population and can be utilized as a powerful tool for forensic applications. In addition, population comparisons demonstrated that the genetic similarities widely existed among Han Chinese populations distributed in different administrative divisions, and genetic differences had existed between minorities (most prominently for Uyghur and Kazakh) and Han groups.

Population data and forensic efficiency of 21 autosomal STR loci included in AGCU EX22 amplification system in the Wanzhou Han population

Autosomal short tandem repeats (STRs), widely distributed in the whole human genome, play an important role in personal identification and parentage testing. In this study, the allele frequencies and forensic efficiency parameters of 21 autosomal STR loci included in the AGCU EX22 kit were obtained from 433 Chinese Han individuals residing in the Wanzhou District in the north of Chongqing Municipality, Southwest China. No deviation from Hardy-Weinberg equilibrium was observed in all of the 21 STR loci. A total of 241 alleles were observed with allele frequencies ranging from 0.0011 to 0.5418. The cumulative power of discrimination and the cumulative probability of exclusion were 0.9999999999999999999999999 and 0.999999996, respectively. The results of genetic distance, neighbor-joining tree, principal component plots, and multidimensional scaling analysis revealed that the Wanzhou Han had more genetic differences when compared with Kazakh and Uyghur populations from Xinjiang than other included reference populations. In summary, the results in forensic characteristic analyses indicated that the 21 STRs are highly polymorphic and can be served as a useful tool in forensic routine practices. The population comparison indicated that close geographic or ethnic origin groups had a strong genetic affinity with each other.

Genetic diversity of 21 autosomal STR loci in the Han population from Sichuan province, Southwest China

Exploration of the ethnic origin and genetic differentiation of 56 Chinese officially recognized nationalities populations played a fundamental role in the research field of population genetics, forensic science, linguistics, anthropology, and archaeology. In the present study, population data of 21 autosomal STR loci (CSF1PO, D10S1248, D12S391, D13S317, D16S539, D18S51, D19S433, D21S11, D2S1338, D2S441, D3S1358, D5S818, D6S1043, D7S820, D8S1179, FGA, Penta D, Penta E, TH01, TPOX, and vWA) included in the AGCU EX22 kit in 2793 Southwest Han Chinese individuals was obtained and population genetic relationships among 28 Chinese populations were investigated. Our study indicated that the twenty-one autosomal STRs are highly polymorphic in the Sichuan Han population and can be used as a powerful tool in the routine forensic usage. MDS and phylogenetic analysis suggested that the Sichuan Han population kept a close genetic relationship with the southwest populations.