Differential pre‐amplification of STR loci for fragmented forensic DNA profiling

DNA profiling of short tandem repeats (STR) has been successfully used for the identification of individuals in forensic samples, accidents and natural disasters. However, STR profiling of DNA isolated from old crime scenes and damaged biological samples is difficult due to DNA degradation and fragmentation. Here, we show that pre‐amplification of STR loci using biotinylated primers for the STR loci is an efficient strategy to obtain STR profiling results from fragmented forensic samples. Analysis of STR loci with longer amplicon sizes is generally hampered, since these relatively long loci are vulnerable to DNA fragmentation. This problem was overcome by using reduced or increased primer concentrations for loci with shorter or longer amplicon sizes, respectively, in our pre‐amplification strategy. In addition, pre‐amplification of STR loci into two groups of short or long amplicon size increases the efficiency of STR profiling from highly fragmented forensic DNA samples. Therefore, differential pre‐amplification of STR loci is an effective way to obtain DNA profiling results from fragmented forensic samples.     

Integrated massively parallel sequencing of 15 autosomal STRs and Amelogenin using a simplified library preparation approach

Massively parallel sequencing (MPS) technologies, also termed as next‐generation sequencing (NGS), are becoming increasingly popular in study of short tandem repeats (STR). However, current library preparation methods are usually based on ligation or two‐round PCR that requires more steps, making it time‐consuming (about 2 days), laborious and expensive. In this study, a 16‐plex STR typing system was designed with fusion primer strategy based on the Ion Torrent S5 XL platform which could effectively resolve the above challenges for forensic DNA database‐type samples (bloodstains, saliva stains, etc.). The efficiency of this system was tested in 253 Han Chinese participants. The libraries were prepared without DNA isolation and adapter ligation, and the whole process only required approximately 5 h. The proportion of thoroughly genotyped samples in which all the 16 loci were successfully genotyped was 86% (220/256). Of the samples, 99.7% showed 100% concordance between NGS‐based STR typing and capillary electrophoresis (CE)‐based STR typing. The inconsistency might have been caused by off‐ladder alleles and mutations in primer binding sites. Overall, this panel enabled the large‐scale genotyping of the DNA samples with controlled quality and quantity because it is a simple, operation‐friendly process flow that saves labor, time and costs.     

Effects of fingerprint development reagents on subsequent DNA analysis

A variety of evidences are found at crime scenes. Fingerprint and DNA evidences are especially important in the process of identifying personal sources. Among evidences found at crime scenes, cigarette butts are important because they might contain both fingerprints and DNA. In this study, latent fingerprints were detected in cigarette butts using 1,8‐diazafluoren‐9‐one (DFO) and 1,2‐Indanedione/zinc chloride (1,2‐IND/Zn). Next, DNA extraction and real‐time qPCR were performed to quantify and identify the DNA present. Short tandem repeat (STR) profiling was also performed. The results showed that the quantity of DNA recovered was decreased by 16% in DFO‐treated cigarettes and by 27% in 1,2‐IND/Zn‐treated cigarettes when compared to untreated controls. When the STR profiling results were compared with those of the control sample, DFO, and 1,2‐IND/Zn reagent‐treated DNA samples showed individualized genotyping at several loci. Results of this study showed that when cigarette butts were found, DFO and 1,2‐IND/Zn reagents could be used for DNA profiling after fingerprint identification. However, the effect of DFO on STR profiling was less than that of 1,2‐IND/Zn. Therefore, we recommend the use of DFO for fingerprinting cigarette butts if further DNA processing is planned.     

Development of a novel forensic STR multiplex for ancestry analysis and extended identity testing

There is growing interest in developing additional DNA typing techniques to provide better investigative leads in forensic analysis. These include inference of genetic ancestry and prediction of common physical characteristics of DNA donors. To date, forensic ancestry analysis has centered on population‐divergent SNPs but these binary loci cannot reliably detect DNA mixtures, common in forensic samples. Furthermore, STR genotypes, forming the principal DNA profiling system, are not routinely combined with forensic SNPs to strengthen frequency data available for ancestry inference. We report development of a 12‐STR multiplex composed of ancestry informative marker STRs (AIM‐STRs) selected from 434 tetranucleotide repeat loci. We adapted our online Bayesian classifier for AIM‐SNPs: Snipper, to handle multiallele STR data using frequency‐based training sets. We assessed the ability of the 12‐plex AIM‐STRs to differentiate CEPH Human Genome Diversity Panel populations, plus their informativeness combined with established forensic STRs and AIM‐SNPs. We found combining STRs and SNPs improves the success rate of ancestry assignments while providing a reliable mixture detection system lacking from SNP analysis alone. As the 12 STRs generally show a broad range of alleles in all populations, they provide highly informative supplementary STRs for extended relationship testing and identification of missing persons with incomplete reference pedigrees. Lastly, mixed marker approaches (combining STRs with binary loci) for simple ancestry inference tests beyond forensic analysis bring advantages and we discuss the genotyping options available.     

A novel,integrated forensic microdevice on a rotation‐driven platform: Buccal swab to STR product in less than 2 h

This work describes the development of a novel microdevice for forensic DNA processing of reference swabs. This microdevice incorporates an enzyme‐based assay for DNA preparation, which allows for faster processing times and reduced sample handling. Infrared‐mediated PCR (IR‐PCR) is used for STR amplification using a custom reaction mixture, allowing for amplification of STR loci in 45 min while circumventing the limitations of traditional block thermocyclers. Uniquely positioned valves coupled with a simple rotational platform are used to exert fluidic control, eliminating the need for bulky external equipment. All microdevices were fabricated using laser ablation and thermal bonding of PMMA layers. Using this microdevice, the enzyme‐mediated DNA liberation module produced DNA yields similar to or higher than those produced using the traditional (tube‐based) protocol. Initial microdevice IR‐PCR experiments to test the amplification module and reaction (using Phusion Flash/SpeedSTAR) generated near‐full profiles that suffered from interlocus peak imbalance and poor adenylation (significant ?A). However, subsequent attempts using KAPA 2G and Pfu Ultra polymerases generated full STR profiles with improved interlocus balance and the expected adenylated product. A fully integrated run designed to test microfluidic control successfully generated CE‐ready STR amplicons in less than 2 h (<1 h of hands‐on time). Using this approach, high‐quality STR profiles were developed that were consistent with those produced using conventional DNA purification and STR amplification methods. This method is a smaller, more elegant solution than current microdevice methods and offers a cheaper, hands‐free, closed‐system alternative to traditional forensic methods.     

The development of miniSTRs as a method for high-speed direct PCR

There are situations in which it would be very valuable to have a DNA profile within a short time; for example, in mass disasters or airport security. In previous work, we have promoted reduced size STR amplicons for the analysis of degraded DNA. We also noticed that shorter amplicons are more robust during amplification, making them inhibition resistant, and potentially applicable to high-speed direct PCR. Here, we describe a set of miniSTRs capable of rapid direct PCR amplification. The selected markers are a subset of the Combined DNA Index System (CODIS) loci modified to permit high-speed amplification. Using the proposed protocol, the amplification of eight loci plus amelogenin directly from a saliva sample can be completed in 7 min and 38 s using a two-step PCR with 30 cycles of 98°C for 2 s and 62°C for 7 s on a Streck Philisa thermocycler. Selection of DNA polymerase, optimization of the two-step PCR cycling conditions, the primer concentrations, and the dilution of saliva is described. This method shows great potential as a quick screening method to obtain a presumptive DNA profile when time is limited, particularly when combined with high-speed separation and detection methods.     

Developmental validation of the Microreader™ 20A ID system

The Microreader? 20A ID system is designed for forensic applications such as personal identification, parentage testing, and research. It includes 13 combined DNA index system (CODIS) short tandem repeat (STR) loci (CSF1PO, FGA, TH01, TPOX, vWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, and D21S11), three expanded CODIS STR loci (D12S391, D19S433, and D2S1338), three non‐CODIS STR loci (D6S1043, Penta D, and Penta E), and the amelogenin locus in one reaction with a six‐dye fluorescent (FAM, HEX, TAMAR, ROX, PUR, and QD550) analysis system. In this study, the Microreader? 20A ID system was validated according to the Scientific Working Group on DNA Analysis Methods validation guidelines for forensic DNA Analysis methods and Chinese national standard, including PCR‐based studies, sensitivity study, precision, and accuracy evaluation, stutter calculation, inhibitor tests, species specificity, and DNA mixture studies. Our results suggest that the Microreader? 20A ID system is a useful tool for personal identification and parentage testing.     

Sample stacking capillary electrophoretic microdevice for highly sensitive mini Y short tandem repeat genotyping

Lab‐on‐a‐chip provides an ideal platform for short tandem repeat (STR) genotyping due to its intrinsic low sample consumption, rapid analysis, and high‐throughput capability. One of the challenges, however, in the forensic human identification on the microdevice is the detection sensitivity derived from the nanoliter volume sample handling. To overcome such a sensitivity issue, here we developed a sample stacking CE microdevice for mini Y STR genotyping. The mini Y STR includes redesigned primer sequences to generate smaller‐sized PCR amplicons to enhance the PCR efficiency and the success rate for a low copy number and degraded DNA. The mini Y STR amplicons occupied in the 5‐ and 10‐mm stacking microchannels are preconcentrated efficiently in a defined narrow region through the optimized sample stacking CE scheme, resulting in more than tenfold improved fluorescence peak intensities compared with that of a conventional cross‐injection microcapillary electrophoresis method. Such signal enhancement allows us to successfully analyze the Y STR typing with only 25 pg of male genomic DNA, with high background of female genomic DNA, and with highly degraded male genomic DNA. The combination of the mini Y STR system with the novel sample stacking CE microdevice provides the highly sensitive Y STR typing on a chip, making it promising to perform high‐performance on‐site forensic human identification.     

A rapid nuclear staining test using cationic dyes contributes to efficient STR analysis of telogen hair roots

Telogen hairs presented in the crime scene are commonly encountered as trace evidence. However, short tandem repeat (STR) profiling of the hairs currently have low and limited use due to poor success rate. To increase the success rate of STR profiling of telogen hairs, we developed a rapid and cost‐effective method to estimate the number of nuclei in the hair roots. Five cationic dyes, Methyl green (MG), Harris hematoxylin (HH), Methylene blue (MB), Toluidine blue (TB), and Safranin O (SO) were evaluated in this study. We conducted a screening test based on microscopy and the percentage of loss with nuclear DNA, in order to select the best dye. MG was selected based on its specific nuclei staining and low adverse effect on the hair‐associated nuclear DNA. We examined 330 scalp and 100 pubic telogen hairs with MG. Stained hairs were classified into five groups and analyzed by STR. The fast staining method revealed 70% (head hair) and 33.4% (pubic hair) of full (30 alleles) and high partial (18–29 alleles) STR profiling proportion from the lowest nuclei count group (one to ten nuclei). The results of this study demonstrated a rapid, specific, nondestructive, and high yield DNA profiling method applicable for screening telogen hairs.     

Development of a new 25plex STRs typing system for forensic application

We have developed a novel STR 25‐plex florescence multiplex‐STR kit (DNATyper25) to genotype 23 autosomal and two sex‐linked loci for forensic applications and paternity analysis. Of the 23 autosomal loci, 20 are non‐CODIS. The sex‐linked markers include a Y‐STR locus (DYS391) and the Amelogenin gene. We present developmental validation studies to show that the DNATyper25 kit is reproducible, accurate, sensitive, and robust. Sensitivity testing showed that full profiles were achieved with as low as 125 pg of human DNA. Specificity testing demonstrated a lack of cross reactivity with a variety of commonly encountered non‐human DNA contaminants. Stability testing showed that full profiles were obtained with humic acid concentration ≤60 ng/μL and hematin concentration <400 μM. For forensic evaluation, the 23 autosomal STRs followed the Hardy–Weinberg equilibrium. In an analysis of 509 Chinese (CN) Hans, we detected a combined total of 181 alleles at the 23 autosomal STR loci. Since these autosomal STRs are independent from one another, PM was 8.4528 × 10^?22, TDP was 0.999 999 999 999 999 999 999, CEP was 0.999 999 8395. The forensic efficiency parameters demonstrated that these autosomal STRs are highly polymorphic and informative in the Han population of China. We performed population comparisons and showed that the Northern CN Han has a close genetic relationship with the Luzhou Han, Tujia, and Bai populations. We propose that the DNATyper25 kit will be useful for cases where paternity analysis is difficult and for situations where DNA samples are limited in quantity and low in quality.     

A powerful,novel, multiplex typing system for six short tandem repeat loci and the allele frequency distributions in two Japanese regional populations

A new multiplex system for six tetranucleotide short tandem repeat (STR) loci was devised based on multicolor dye technology. Six loci (D20S480, D6S2439, D6S1056, D9S1118, D4S2639, and D17S1290), each with high discriminating power (each unbiased estimates of expected heterozygosity, Exp. Hz, > 0.80 in a preliminary test), were selected from more than 100 tetranucleotide STRs included in a commercially available primer set. These loci were also selected so as not to link with general STRs in commercially released kits including the combined DNA index system (CODIS) 13 core STRs. The primers were newly designed in the present study, in which each amplicon size had a range of less than 200 base pairs (bp), in order to genotype from highly degraded template DNA. Using this system, we genotyped 270 Honshu (mainland)-Japanese and 187 Okinawa-Japanese. From these allele frequencies, we performed three tests, a homozygosity test, a likelihood ratio test and an exact test for Hardy-Weinberg equilibrium (HWE), and no significant deviations (p < 0.05) from HWE were observed. We also compared the allele distributions at six STRs between both populations, and they were significantly different (p < 0.05) at three loci (D6S2439, D9S1118 and D4S2639). Furthermore, the Exp. Hz and the power of discrimination (PD) at all loci in the Honshu-Japanese population were higher than 0.80 and 0.93, respectively. These statistical values for discriminating power in the Honshu-Japanese were almost the same as in the Okinawa-Japanese. This novel, multiplex polymerase chain reaction (PCR) amplification and typing system for six STR loci thus promises to be a convenient and informative new DNA profiling system in the forensic field.     

Infrared fluorescent automated detection of thirteen short tandem repeat polymorphisms and one gender-determining system of the CODIS core system

We used an infrared (IR) automated fluorescence monolaser sequencer for the analysis of 13 autosomal short tandem repeat (STR) systems (TPOX, D3S1358, FGA, CSF1PO, D5S818, D7S820, D8S1179, TH01, vWA, D13S317, D16S359, D18S51, D21S11) and the X-Y homologous gene amelogenin system. These two systems represent the core of the combined DNA index systems (CODIS). Four independent multiplex reactions, based on the polymerase chain reaction (PCR) technique and on the direct labeling of the forward primer of every primer pair, with a new molecule (IRDye800), were set up, permitting the exact characterization of the alleles by comparison with ladders of specific sequenced alleles. This is the first report of the whole analysis of the STRs of the CODIS core using an IR automated DNA sequencer. The protocol was used to solve paternity/maternity tests and for population studies. The electrophoretic system also proved useful for the correct typing of those loci differing in size by only 2 bp. A sensibility study demonstrated that the test can detect an average of 10 pg of undegraded human DNA. We also performed a preliminary study analyzing some forensic samples and mixed stains, which suggested the usefulness of using this analytical system for human identification as well as for forensic purposes.     

17 to 23: A novel complementary mini Y‐STR panel to extend the Y‐STR databases from 17 to 23 markers for forensic purposes

A Y‐STR multiplex system has been developed with the purpose of complementing the widely used 17 Y‐STR haplotyping (AmpFlSTR Y Filer® PCR Amplification kit) routinely employed in forensic and population genetic studies. This new multiplex system includes six additional STR loci (DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643) to reach the 23 Y‐STR of the PowerPlex® Y23 System. In addition, this kit includes the DYS456 and DYS385 loci for traceability purposes. Male samples from 625 individuals from ten worldwide populations were genotyped, including three sample sets from populations previously published with the 17 Y‐STR system to expand their current data. Validation studies demonstrated good performance of the panel set in terms of concordance, sensitivity, and stability in the presence of inhibitors and artificially degraded DNA. The results obtained for haplotype diversity and discrimination capacity with this multiplex system were considerably high, providing further evidences of the suitability of this novel Y‐STR system for forensic purposes. Thus, the use of this multiplex for samples previously genotyped with 17 Y‐STRs will be an efficient and low‐cost alternative to complete the set of 23 Y‐STRs and improve allele databases for population and forensic purposes.     

Evaluation of whole-genome amplification of low-copy-number DNA in chimerism analysis after allogeneic stem cell transplantation using STR marker typing

Whole-genome DNA amplification (WGA) is a promising method that generates large amounts of DNA from samples of limited quantity. We investigated the accuracy of a multiplex PCR approach to WGA over STR loci. The amplification bias within a locus and over all analyzed loci was investigated in relation to the amount of template in the WGA reaction, the specific STR locus, and allele length. We observed reproducible error-free STR profiles with 10 ng down to 1 ng of DNA template. The amplification deviation at a locus and between loci was within the intra-method reproducibility. WGA is the method of choice for amplifying nanogram amounts of genomic DNA for different applications. We detected unbalanced STR amplifications at one locus and between loci, allelic drop-outs, and additional alleles after WGA of low-copy-number DNA. We found that the high number of drop-outs and drop-ins could be eradicated using pooled DNA from separate WGA reactions even with as little as 100 pg of starting template. Nevertheless, the quality of the results was still not sufficient for use in routine chimerism analysis of limited specific cell populations after allogeneic stem cell transplantation.     

Genetic profile characterization and population study of 21 autosomal STR in Chinese Kazak ethnic minority group

Short tandem repeat loci have been recognized as useful tools in the routine forensic application and in recent decades, more and more new short tandem repeat (STR) loci have been constantly discovered, studied, and applied in forensic caseworks. In this study, we investigated the genetic polymorphisms of 21 STR loci in the Kazak ethnic minority as well as the genetic relationships between the Kazak ethnic minority and other populations. Allelic frequencies of 21 STR loci were obtained from 114 unrelated healthy Kazak individuals in the Ili Kazak Autonomous Prefecture, Xinjiang Uigur Autonomous Region of China. We observed a total of 159 alleles in the group with the allelic diversity values ranging from 0.0044 to 0.5088. The highest polymorphism was found at D19S433 locus and the lowest was found at D1S1627. Statistical analysis of the generated data indicated no deviation from Hardy–Weinberg equilibriums at all 21 STR loci. In order to estimate the population differentiation, allelic frequencies of all STR loci of the Kazak were compared with those of other neighboring populations using analysis of molecular variance method. Statistically significant differences were found between the studied population and other populations at 2–7 STR loci. A neighbor‐joining tree was constructed based on allelic frequencies of the 21 STR loci and phylogenetic analysis indicates that the Kazak has a close genetic relationship with the Uigur ethnic group. The present results may provide useful information for forensic sciences and population genetics studies, and can also increase our understanding of the genetic background of this group. The present findings showed that all the 21 STR loci are highly genetically polymorphic in the Kazak group, which provided valuable population genetic data for the genetic information study, forensic human individual identification, and paternity tests.     

Cover Picture: Electrophoresis 21'2010

Issue no. 21 is a regular issue with "Emphasis on Nucleic Acids" and comprises 17 contributions distributed over 4 distinct parts. Part I is on nucleic acids and has 8 research articles on various aspects of nucleic acid research including an automated instrument for human STR identification, a high resolution chip‐CE assay for rapid detection of gene mutations and amplifications, a fluorescence‐based sequence‐specific primer PCR, pulsed field CE for RNA separation, methylated DNA immunoprecipitation sequencing, PCR‐SSCP, DNA methylation, and analysis of SNPs. Part II has 4 research articles dealing with studies on protein and proteomics analysis, e.g., microchip IEF, CE analysis of microheterogeneous glutelin subunits in rice, protein precipitation methods and prefractionation of plasma for proteomic analysis. Part III has 2 contributions that describe the separation of the enantiomers of DL‐isocitric acid by CE and the analysis of trace degradation products of S‐adenosylmethionine, which are decarboxylated diastereomers, by CE. The last 3 articles in this issue (Part IV) are on novel methodologies for facile interfacing of CE with MS, electrokinetic chromatography for the determination of contaminants and impurities of heparin samples, and particle electrophoresis. As such, issue no. 21 is packed with the latest developments and innovations in the field. Featured articles include: An automated instrument for Human STR identification: design, characterization, and experimental validation (doi: 10.1002/elps.201000305 )) Miniature flowing atmospheric‐pressure afterglow ion source for facile interfacing of capillary electrophoresis with mass spectrometry (doi: 10.1002/elps.201000350 )) Capillary electrophoresis for analysis of microheterogeneous glutelin subunits in rice (Oryza sativa L.). (doi: 10.1002/elps.201000333 ))     

A modular microfluidic system for deoxyribonucleic acid identification by short tandem repeat analysis

Microfluidic technology has been utilized in the development of a modular system for DNA identification through STR (short tandem repeat) analysis, reducing the total analysis time from the ∼6 h required with conventional approaches to less than 3 h. Results demonstrate the utilization of microfluidic devices for the purification, amplification, separation and detection of 9 loci associated with a commercially-available miniSTR amplification kit commonly used in the forensic community. First, DNA from buccal swabs purified in a microdevice was proven amplifiable for the 9 miniSTR loci via infrared (IR)-mediated PCR (polymerase chain reaction) on a microdevice. Microchip electrophoresis (ME) was then demonstrated as an effective method for the separation and detection of the chip-purified and chip-amplified DNA with results equivalent to those obtained using conventional separation methods on an ABI 310 Genetic Analyzer. The 3-chip system presented here demonstrates development of a modular, microfluidic system for STR analysis, allowing for user-discretion as to how to proceed after each process during the analysis of forensic casework samples.     

Mutation rate analysis at 19 autosomal microsatellites

Previous studies have demonstrated that a large sample size is needed to reliably estimate population‐ and locus‐specific microsatellite mutation rates. Therefore, we conducted a long‐term collaboration study and performed a comprehensive analysis on the mutation characteristics of 19 autosomal short tandem repeat (STR) loci. The STR loci located on 15 of 22 autosomal chromosomes were analyzed in a total of 21 106 samples (11 468 parent–child meioses) in a Chinese population. This provided 217 892 allele transfers at 19 STR loci. An overall mutation rate of 1.20 × 10^?3 (95% CI, 1.06–1.36 × 10^?3) was observed in the populations across 18 of 19 STR loci, except for the TH01 locus with no mutation found. Most STR mutations (97.7%) were single‐step mutations, and only a few mutations (2.30%) comprised two and multiple steps. Interestingly, approximately 93% of mutation events occur in the male germline. The mutation ratios increased with the paternal age at child birth (r = 0.99, p<0.05), but not maternal age. Last, with the combination analysis of the data from the southern Chinese population, we drew a picture of 19 STR mutations in China. In conclusion, the data from this study will provide useful information in parentage testing, kinship analysis, and population genetics.     

Genetic diversity and haplotype structure of 24 Y‐chromosomal STR in Chinese Hui ethnic group and its genetic relationships with other populations

In the present study, 24 Y‐chromosomal short tandem repeat (Y‐STR) loci were analyzed in 115 unrelated Hui male individuals from Haiyuan county or Tongxin county, Ningxia Hui Autonomous Region, China, to evaluate the forensic application of the 24 STR loci and to analyze interpopulation differentiations by making comparisons between the Hui group data and previously published data of other 13 populations. A total of 115 different haplotypes were observed on these 24 Y‐STR loci. The gene diversities ranged from 0.4049 (DYS437) to 0.9729 (DYS385a, b). The overall haplotype diversity was 1 at AGCU 24 Y‐STR loci level, while the values were reduced to 0.999237, 0.996949, and 0.996644 at the Y‐filer 17 loci, 11 Y‐STR loci of extended haplotype and 9 Y‐STR loci of minimal haplotype levels, respectively; whereas, haplotype diversity for additional 7 loci (not included in Y‐filer 17 loci) was 0.995271. The pairwise F_ST, multidimensional scaling plot and neighbor‐joining tree indicated the Hui group had the closest genetic relationship with Sala in the paternal lineage in the present study. In summary, the results in our study indicated the 24 Y‐STRs had a high level of polymorphism in Hui group and hence could be a powerful tool for forensic application and population genetic study.     

24 Y‐chromosomal STR haplotypic polymorphisms for Chinese Uygur ethnic group and its phylogenic analysis with other Chinese groups

The Uygur ethnic minority is the largest ethnic group in the Xinjiang Uygur Autonomous Region of China, and is a precious resource for the study of ethnogeny and forensic biology. Previous studies have focused on the genetic background of the Uygur group, however, the patrilineal descent of the group is still unclear. In this study, we investigated the genetic diversity of 24 Y‐STR loci in the Uygur group and analyzed the population differentiations as well as the genetic relationships between the Uygur group and other previously reported populations using 17 Y‐filer loci. According to haplotypic analysis of the 24 Y‐STR loci in 109 Uygur individuals, 104 different haplotypes were obtained, 99 of which were unique. The haplotypic diversity and discrimination capacity of these 24 Y‐STR loci in Uygur group were 0.9992 and 0.9541, respectively. An additional 7 loci (DYS388, DYS444, DYS447, DYS449, DYS522, and DYS527a,b) showed high genetic diversity and improved the overall discrimination capacity of the 24 Y‐STR system. Pairwise Fst and neighbor‐joining analysis showed that the Uygur group was genetically close to the Han populations from different regions.