Using two self-developed InDel panels to explore forensic traits and ancestral components in the Hui group.

To address the challenges faced by forensic examiners in degraded DNA analysis, we have developed two different panels for various forensic applications, encompassing an AIM-InDel panel for ancestry inference and a Multi-InDel panel for individual identification, respectively. Herein, the efficiencies of these two panels were tested in the Chinese Hui group. By calculating forensic parameters and simulating family relationships, we verified that the Multi-InDel panel could be an effective tool for individual identification, paternity testing, and could assist in kinship identification in the Hui group. For full siblings, the true positive rate of kinship discrimination was 96.553%, when the threshold of log10LR was 1. The cumulative probability of matching as well as cumulative probability of exclusion were 3.8117 × 10-26 and 0.999999722, respectively. Meanwhile, we found that the AIM-InDel panel was effective for bio-geographic ancestry inference, with the vast majority of loci contributing significantly to distinguish East Asian, African, and European populations. By studying the population structure of the Hui ethnic minority, the genetic distance to the Beijing Han population was the closest among the 26 reference populations, which was similar to previous reports. In summary, we have developed two panels which can be effectively applied to the Hui group for individual identification, parentage testing and bio-geographic ancestry inference.

Investigating the effectiveness of forensic genetics and population genetic diversity using a multi-InDel system in Chinese Hezhou and Southern Shaanxi Han populations.

INTRODUCTION: Multiple insertion-deletion (multi-InDel) has greater potential in forensic genetics than InDel, and its efficacy in kinship testing, individual identification, DNA mixture detection and ancestry inference remains to be explored. METHODS: Consequently, we designed an efficient and robust system consisting of 41 multi-InDels to evaluate its efficacy in forensic applications in Chinese Hezhou Han (HZH) and Southern Shaanxi Han (SNH) populations and explore the genetic relationships between the SNH, HZH, and 26 reference populations. RESULTS AND CONCLUSION: The obtained results showed that 38 out of the 41 multi-InDels had fairly high genetic variations. The the cumulative probability of discrimination and exclusion values of the multi-InDels (except MI38) in HZH and SNH populations both exceeded 1-e-25 and 1-e-6, correspondingly. The genetic compositions of HZH and SNH individuals were similar to that of East Asians and the Naive Bayes model could well distinguish East Asians, Africans and Americans. These results indicated that the multi-InDel systerm can serve as an effective tool to provide important evidence for the development of multi-InDels in forensic practice and better analyse the genetic background of the Han Chinese populations.

Developmental validation of a custom-designed Multi-InDel panel: A five-dye multiplex amplification system for challenging DNA samples.

The continual investigation of novel genetic markers has yielded promising solutions for addressing the challenges encountered in forensic DNA analysis. In this study, we have introduced a custom-designed panel capable of simultaneously amplifying 41 novel Multi-insertion/deletion (Multi-InDel) markers and an amelogenin locus using the capillary electrophoresis platform. Through a developmental validation study conducted in accordance with guidelines recommended by the Scientific Working Group on DNA Analysis Methods, we demonstrated that the new Multi-InDel system exhibited the sensitivity to produce reliable genotyping profiles with as little as 62.5 pg of template DNA. Accurate and complete genotyping profiles could be obtained even in the presence of specific concentrations of PCR inhibitors. Furthermore, the maximum amplicon size for this system was limited to under 220 bp in the genotyping profile, resulting in its superior efficiency compared to commercially available short tandem repeat kits for both naturally and artificially degraded samples. In the context of mixed DNA analysis, the Multi-InDel system was proved informative in the identification of two-person DNA mixture, even when the template DNA of the minor contributor was as low as 50 pg. In conclusion, a series of performance evaluation studies have provided compelling evidence that the new Multi-InDel system holds promise as a valuable tool for forensic DNA analysis.

Targeted sequencing of high-density SNPs provides an enhanced tool for forensic applications and genetic landscape exploration in Chinese Korean ethnic group.

BACKGROUND: In this study, we present a NGS-based panel designed for sequencing 1993 SNP loci for forensic DNA investigation. This panel addresses unique challenges encountered in forensic practice and allows for a comprehensive population genetic study of the Chinese Korean ethnic group. To achieve this, we combine our results with datasets from the 1000 Genomes Project and the Human Genome Diversity Panel. RESULTS: We demonstrate that this panel is a reliable tool for individual identification and parentage testing, even when dealing with degraded DNA samples featuring exceedingly low SNP detection rates. The performance of this panel for complex kinship determinations, such as half-sibling and grandparent-grandchild scenarios, is also validated by various kinship simulations. Population genetic studies indicate that this panel can uncover population substructures on both global and regional scales. Notably, the Han population can be distinguished from the ethnic minorities in the northern and southern regions of East Asia, suggesting its potential for regional ancestry inference. Furthermore, we highlight that the Chinese Korean ethnic group, along with various Han populations from different regional areas and certain northern ethnic minorities (Daur, Tujia, Japanese, Mongolian, Xibo), exhibit a higher degree of genetic affinities when examined from a genomic perspective. CONCLUSION: This study provides convincing evidence that the NGS-based panel can serve as a reliable tool for various forensic applications. Moreover, it has helped to enhance our knowledge about the genetic landscape of the Chinese Korean ethnic group.

A self-developed AIM-InDel panel designed for degraded DNA analysis: Forensic application characterization and genetic landscape investigation in the Han Chinese population.

To assist in forensic DNA investigation, we developed a new panel capable of simultaneously amplifying 56 ancestry-informative InDels, three Y-InDels and the Amelogenin locus in one PCR reaction. The fragment lengths of the InDel amplicons in this panel were restricted to <200 bp to benefit degraded DNA analysis. In this study, we explored the efficiency of this new panel for forensic applications in the Han Chinese population, and further shed light on the genetic structures of Han populations. We showed that the new panel could be served as an efficient tool for ancestry inference of intercontinental populations. Especially, the Han individuals in different regions could be 100% correctly predicted to be of East Asian origin with this new panel. The Han populations in different regions shared similar ancestry components in their genetic structures. Besides, we also revealed that the new panle could be useful for individual identification in different Han Chinese populations. In conclusion, we have provided the necessary evidence that the self-constructed new panel could play an important role in forensic DNA investigation.

Analysis of factors influencing the determination of indications for allergen-specific immunotherapy.

OBJECTIVE: To develop a questionnaire and a scoring system for evaluating physicians' knowledge of allergen immunotherapy (AIT). METHODS: Questionnaire was designed using the Questionnaire Star tool. A total of 1024 physicians were assessed, and based on the score divided into accurate judgment and inaccurate judgment groups. Statistical analysis was done, and counting data were expressed as frequencies and percentage values. Chi-square test and multi-factor logistic analysis were used to determine influencing factors on the indications for AIT. RESULTS: Physician's age, grade of the hospital, and pediatric specialty influenced the accurate judgment of AIT indication after adjustment for independent variables (P < 0.05). In all, 80.5% physicians exercised accurate assessment for allergic rhinitis. Allergic conjunctivitis was judged accurately by 47.0% physicians. Bronchial asthma was judged accurately by 71.0% physicians, and atopic dermatitis by 61.3% physicians, with a higher accuracy rate for pediatricians than nonpediatricians for all the mentioned conditions (P < 0.05). There was no significant difference in the accuracy of judgment between pediatricians and non-pediatricians in terms of AIT for food allergy and dust mite sensitization (P > 0.05). CONCLUSION: The results of our study demonstrated a high accuracy judgment rate among clinicians for rhinitis, asthma, and dermatitis, and a low accuracy rate for desensitization of healthy people with allergic conjunctivitis, food allergies, and allergen sensitization.

High resolution HLA-DRB1 analysis and shared molecular amino acid signature of DRß1 molecules in Occult hepatitis B infection.

AIM: To investigate the association of human leukocyte antigen (HLA)-DRB1 alleles and the variations of polymorphic amino acid changes in DRß1 chain in Shaanxi Han population with Occult hepatitis B infection (OBI). METHODS: High-resolution HLA-DRB1 genotyping was performed in 107 OBI carriers and 280 normal controls. Sequence information was used to assign which amino acids were encoded at all polymorphic positions. Three-dimensional modeling was performed to explore the effect of the key residues on the HLA-DRB1 molecule. RESULTS: Strong susceptible association for allele DRB1*07:01 was observed in OBI carriers. The amino acid variation at HLA-DRß1 molecule revealed susceptible associations for residues Gln4ß, Val57ß(P9), Ser60ß(P9) and Val78ß(P4), the amino acids Arg4ß, Asp57ß(P9), Tyr60ß(P9) and Tyr78ß(P4) showed protective associations. CONCLUSION: Alleles DRB1*07:01 showed strong susceptible associations in OBI carriers. The amino acid variations in DRß molecules revealed significant molecular markers for susceptibility and protection from OBI in Shaanxi Han population.

Human leukocyte antigen class I association with occult hepatitis B virus infection in the Shaanxi Han group: Analysis at the haplotype level.

BACKGROUND: Human leucocyte antigen (HLA) class I genes and haplotypes correlate with hepatitis B virus (HBV) infection. Occult HBV infection (OBI), a special type of chronic HBV infection, is defined as HBV surface antigen negative patients with or those without serologic markers by the means of HBV DNA detection in human plasma or in liver tissue by a diagnostic test. So far, the associations of HLA I haplotypes with OBI have not been reported previously in China. METHODS: A case-control study between 107 OBI subjects and 280 healthy controls from blood donors in the Blood Center of the Shaanxi Province was conducted in the present association analysis. The HLA-A, -B and -C loci of case-control subjects were detected and genotyped by polymerase chain reaction-sequence based typing. The HLA-A, -B and -C haplotypic frequencies were calculated by the maximum likelihood method. RESULTS: The HLA-A*33:03-C*07:01G (pc = 0.039, odds ratio [OR] = 8.996, 95% confidence interval [CI] = 1.825-44.338), B*44:03-C*07:01G (pc = 0.0069, OR = 12.000, 95% CI = 2.507-57.436) and A*33:03-B*44:03-C*07:01G (pc = 0.04, OR = 7.094, 95% CI = 1.387-36.288) haplotypes showed a a significant positive association with OBI. Independent effects demonstrated that HLA-B*44:03 and HLA-C*07:01G gave the main contribution to risk, whereas HLA-A*33:03 was associated only by linkage disequilibrium. CONCLUSIONS: This present study is the first to demonstrate that HLA I haplotypes are associated with OBI in the Shaanxi Han population. The present results suggest that HLA-B*44:03-C*07:01G might be a potential risk factor for OBI. Comparisons of the frequencies of HLA I haplotypes at high resolution were made between OBI from northern Chinese Han and controls. Frequencies of HLA-A-B, A-C, B-C, A-B-C between the OBI group (gray column) and the control group (blank column) were compared. Haplotypes with p < 0.05 in either group were shown. p values for multiple comparisons (pc ) were corrected by Bonferroni correction (*pc  < 0.05).

Insights into AIM-InDel diversities in Yunnan Miao and Hani ethnic groups of China for forensic and population genetic purposes.

BACKGROUND: Ancestry informative markers are regarded as useful tools for inferring the ancestral information of an individual, which have been widely used in the criminal investigations and population genetic studies. Previously, a multiplex amplification panel containing 39 AIM-InDel loci was constructed. This study aims to investigate the genetic polymorphisms of these 39 AIM-InDel loci in Yunnan Hani and Miao ethnic groups, and to uncover their genetic affinities with reference populations based on the AIM-InDel markers. MATERIALS AND METHODS: In this research, 39 AIM-InDel profiles of 203 unrelated Miao individuals and 203 unrelated Hani individuals in Yunnan province of China were acquired. Additionally, we evaluated the genetic polymorphisms of 39 InDel loci in Yunnan Miao and Hani groups. Moreover, the genetic relationships among Yunnan Miao, Hani and reference populations were also clarified based on Nei's genetic distances, pairwise fixation indexes, principal component analyses, phylogenetic analyses, and STRUCTURE analyses. RESULTS: Genetic diversity analyses demonstrated that these InDel loci showed varying degrees of genetic polymorphisms, and could be utilized in forensic identifications in Yunnan Miao and Hani groups. The results of principal component analyses, phylogenetic analyses and Structure analyses revealed that Yunnan Miao and Hani groups had closer genetic relationships with East Asian populations, especially with the populations from Southern China. This research enriched the genetic data of Chinese ethnic minority, and provided ancestral information of Yunnan Miao and Hani groups from the perspective of population genetics.

Developmental validations of a self-developed 39 AIM-InDel panel and its forensic efficiency evaluations in the Shaanxi Han population.

Most of insertion/deletion polymorphisms are diallelic molecular markers characterized as small amplicon sizes, high inter-population diversities, and low mutation rates, which make them the promising genetic markers in biogeographic ancestor inference field. The developmental validations of a 39 ancestry informative marker-insertion/deletion (AIM-InDel) panel and the genetic polymorphic investigations of this panel were performed in the Shaanxi Han population of China. The developmental validation included the optimizations of PCR-related indicators, repeatability, reproducibility, precision, accuracy, sensitivity, species specificity, stability of the panel, and the abilities in analyzing degraded, casework, and mixture samples, and the present results demonstrated that this 39 AIM-InDel panel was robust, sensitive, and accurate. For the population diversity analyses, the combined discrimination power value of 38 AIM-InDel loci except for rs36038238 locus was 0.999999999931257, indicating that this novel panel was highly polymorphic, biogeographic informative, and could be also used in individual identifications in the Shaanxi Han population.

Ancestry inference and admixture component estimations of Chinese Kazak group based on 165 AIM-SNPs via NGS platform.

Predicting the biogeographical ancestries of populations and unknown individuals based on ancestry-informative markers (AIMs) has been widely applied in providing DNA clues to criminal investigations, correcting the factor of population stratification in genome-wide association studies (GWAS), and working as the basis of predicting the externally visible characteristics (EVCs) of individuals. The present study chose Chinese Xinjiang Kazak (XJK) group as research object using a 165 AIM-SNPs panel via next generation sequencing (NGS) technology to reveal its ancestral information and genetic background by referencing the populations' data from 1000 Genomes Phase 3. After the Bonferroni correction, there were no significant deviations at the 165 AIM-SNP loci except two loci with homozygote in the studied XJK group. Ancestry information inference and populations genetic analyses were conducted basing on multiplex statistical methods such as forensic statistical parameter analyses, estimation of the success ratios with cross-validation, population tree, principal component analysis (PCA), and genetic structure analysis. The present results revealed that XJK group had the admixed ancestral components of East Asian and European populations with the ratio of about 62:37.

Ancestry informative DIP loci for dissecting genetic structure and ancestry proportions of Qinghai Tibetan and Tibet Tibetan groups.

Tibetans living in the Qing-Tibet plateau show unique genetic features since they are exposed to the high altitude environment. Accordingly, it is necessary for us to analyze genetic components of the Tibetan groups. Here, genetic structure and ancestry proportions of Tibet Tibetan and Qinghai Tibetan groups are dissected by using a previously published ancestral deletion/insertion polymorphisms (DIPs) panel. Genetic distributions of the analyzed DIPs in both Tibetan groups reveal that some DIPs show relatively balanced frequency distributions with the values ranging from 0.4 to 0.6, implying that these DIPs could be used as individual identification loci for forensic applications in both groups. Besides, the cumulative power of discrimination of the panel also reflects that the panel could serve as a valuable tool for forensic individual identifications in Tibet Tibetan and Qinghai Tibetan groups. Population genetic analyses including principal component analysis, DA genetic distances, phylogenetic tree, and genetic structure reveal that two studied Tibetan groups have closer genetic affiliations with East Asian populations. Genetic differentiation analyses of two Han populations, Xinjiang Uyghur and two Tibetan groups reveal that some DIP loci might be informative for differentiating Uyghurs from the other populations.

Distinguishing three distinct biogeographic regions with an in-house developed 39-AIM-InDel panel and further admixture proportion estimation for Uyghurs.

In the forensic field, ancestry-informative markers (AIMs) showing remarkable allele frequency discrepancies can be useful in deducing the likely ancestral origin of a person or estimating the ancestry component proportions of an admixed population or individual. Diallelic single nucleotide polymorphisms are genetic markers commonly used for ancestry inference, but the genotyping methods of single nucleotide polymorphisms fail to fulfil the demands of cost-effectiveness and simplicity of experimental manipulation. To overcome the limitations, a 39 ancestry-informative insertion/deletion polymorphism multiplex panel was developed in the present study to perform ancestry assignment of individuals from three distinct biogeographic regions (Africa, Europe, East Asia). And in the panel design, we also attempted to incorporate AIM-insertion/deletion polymorphisms exhibiting allelic frequency differences in Han, Uyghur, and Tibetan populations into the multiplex assay, further expecting to provide valuable information for refining ancestry inference within Chinese populations. Statistical analyses were performed to estimate efficiency of this panel in clustering individuals from three continents mentioned above into their corresponding populations, which indicated the potential of the panel in ancestry inference. Besides, we also estimated the ancestral component proportions of Uyghur group and STRUCTURE analysis revealed that Uyghurs from Urumchi city of northern Xinjiang exhibited a distinctly admixed pattern of East Asian and European ancestry components with a ratio of 49:44, reflecting the relatively higher East Asian ancestry component contribution in the gene pool of the Uyghur group.

Mutability analysis towards 21 STR loci included in the AGCU 21 + 1 kit in Chinese Han population.

To further illustrate the mutation traits of 21 autosomal STR loci involved in the newly developed AGCU 21 + 1 kit, randomly selected 485 trios were focused on. We have previously confirmed the biological father-mother-child relationships of these trios. Then matters of mutation rates, steps, and origins of the 21 STR loci were statically analyzed. Results showed 35 mutation events occurred at 16 STR loci of the panel during 20,370 meiosis, and the locus-specific mutation rates ranged from 0.000 to 1.134% (D3S4529), with an overall mutation rate of 1.72 × 10-3 (95%CI, 1.20-2.39 × 10-3). Mutation origins exhibited slight discrepancy between male and female germlines, 18 of the 35 mutation events were verified to be contributed by fathers and 13 by mothers, with origins of the remaining 4 events hardly to be assigned. Furthermore, 77.14% of the mutations were one-step mutation. Currently, portraits on mutability of the STR loci involved in the AGCU 21 + 1 panel were barely reported. In view of this, we conclude our data will enrich the mutation information of the 21 STR loci and provide valuable suggestions in calculating likelihood ratios for mutation-involved parental testing cases.

Evaluation of serum ferritin and thyroid function in the second trimester of pregnancy.

Ferritin is a universal intracellular protein that acts as an iron carrier. Several studies have indicated that iron deficiency affects thyroid function in non-pregnant women. Our objective was to assess the relationship between serum ferritin levels and thyroid function in pregnant women during the second trimester. Pregnant women with sufficient iodine intake and normal antithyroid antibodies during the second trimester were recruited from the obstetric outpatient department of the Fifth People's Hospital of Fudan University. Serum ferritin (SF) levels, thyroid function, anti-thyroid antibodies and vitamin B12 were determined by electrochemiluminescence immunoassay kit. Maternal serum iron (Fe), unsaturated iron binding capacity (UIBC), hemoglobin (Hb), creatinine (Cr), fasting blood glucose (FBG), and alanine aminotransferase (ALT) were also evaluated. Stepwise regressions performed to evaluate the associations between SF and other maternal parameters. In the second trimester, 11.4% pregnant women had a SF concentration less than 12 µg/L, and 7.6% pregnant women were anemic. SF levels were negatively correlated with serum TSH levels (r = -0.219, p < 0.05), and positively correlated with FT4 levels (r = 0.203, p < 0.05). Linear regression analysis showed only SF, age, week of gestation were significant predictors of regression with TSH as the dependent variable (ß: -0.007, -0.059, and 0.118 respectively; all p < 0.05). However consistent relation between the SF levels and FT4 was not observed in stepwise linear regression. Maternal iron status is a determinant of TSH concentrations during pregnancy in pregnant women during the second trimester.

Association of human leukocyte antigen polymorphisms with occult hepatitis B virus infection in a Shaanxi Han population.

BACKGROUND: Occult hepatitis B virus (HBV) infection (OBI) is defined as HBV DNA detection in serum or in the liver by sensitive diagnostic tests in HBV surface antigen (HBsAg) negative patients with or without serologic markers of previous HBV exposure. Because the human leukocyte antigen (HLA) system is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes were the key determinants of HBV persistence and clearance. The present study aimed to calculate the allelic frequency of HLA loci and investigate the association between HLA alleles and the outcome of OBI in Shaanxi Han population in the northwest of China. METHODS: We conducted a case-control study between 107 OBI subjects and 280 healthy control individuals from blood donors of Shaanxi Blood Center. Five HLA loci, including HLA-A,-B,-C,-DRB1 and -DQB1, were selected and further genotyped using a polymerase chain reaction sequence-based typing (SBT) method. RESULTS: Using the chi-squared test, we found that the allele frequencies of HLA-B*44:03 [odds ratios (OR) = 2.146, 95% confidence interval (CI) = 1.070-4.306, p = 0.028]; C*07:01 (OR = 4.693, CI = 1.822-12.086, p = 0.000); DQB1*02:02 (OR = 1.919, CI = 1.188-3.101, p = 0.007); and DRB1*07:01 (OR = 2.012, CI = 1.303-3.107, p = 0.001) were markedly higher in the OBI group compared to the healthy control group. The allele frequencies of HLA-DRB1*08:03 (OR = 0.395, CI = 0.152-1.027, p = 0.049); DRB1*15:01 (OR = 0.495, CI = 0.261-0.940, p = 0.029); and DQB1*06:02 (OR = 0.500, CI = 0.249-1.005, p = 0.048) were obviously lower in the OBI group compared to the healthy control group. These data indicated that HLA-B*44:03, C*07:01, DQB1*02:02 and DRB1*07:01 were related to OBI infection, whereas HLA-DRB1*08:03, DRB1*15:01 and DQB1*06:02 alleles were associated with HBV DNA clearance in a Shaanxi Han population. CONCLUSIONS: The results of the present study suggest that host HLA gene is an important influencing factor for OBI pathogenesis.

Chinese Xibe population genetic composition according to linkage groups of X-chromosomal STRs: population genetic variability and interpopulation comparisons.

BACKGROUND: The Xibe population is one of China's officially recognised populations and is now distributed separately from west to east in the northern part of China. X-chromosomal short tandem repeats have a special inheritance pattern, and could be used as complements in forensic application, especially for complex or deficiency cases. SUBJECTS AND METHODS: This study obtained the allelic and haplotypic frequencies of 19 X-STR loci in the Xibe population from Xinjiang Uygur Autonomous Region, China, and studied the genetic differentiations between the Xibe and other populations. RESULTS: The combined power of discrimination in females and males and mean exclusion chances in deficiency cases, normal trios and duo cases was at least 0.999 999 994. In the haplotypic study, the Xibe population showed a more similar pattern of haplotype distribution with Asian populations than populations from other continents, while allelic study also indicated a closer relationship between the Xibe and Asian populations. CONCLUSIONS: The 19 X-STR loci would be useful in forensic application in the studied population. The Xibe population showed a closer genetic relationship with Asian populations in the study, and more population data would be necessary for more detailed genetic relationship studies.

Allele and haplotype diversity of new multiplex of 19 ChrX-STR loci in Han population from Guanzhong region (China).

X-chromosomal short tandem repeats (X-STRs) have been proved to be useful for some deficiency paternity cases in recent years. Here, we studied the genetic polymorphisms of 19 X-STR loci (DXS10148-DXS10135-DXS8378, DXS10159-DXS10162-DXS10164, DXS7132-DXS10079-DXS10074-DXS10075, DXS6809-DXS6789, DXS7424-DXS101, DXS10103-HPRTB-DXS10101 and DXS7423-DXS10134) in 252 male and 222 female individuals from Guanzhong Han population, China. No deviation for all 19 loci was observed from the Hardy-Weinberg equilibrium. The polymorphism information content values of the panel of 19 loci were more than 0.5 with the exception of the locus DXS7423. The combined power of discrimination were 0.9999999999999999999994340 in females and 0.9999999999997662 in males, respectively; and the combined mean exclusion chances were 0.999999993764 in duos and 0.999999999997444 in trios, respectively. The haplotype diversities for all the seven clusters of linked loci were more than 0.9. The results showed that the panel of 19 X-STR loci were powerful for forensic applications in Guanzhong Han population. Locus by locus population comparisons showed significant differences at more than seven loci between Guanzhong Han population and the groups from North America, Europe and Africa.

Single nucleotide polymorphisms of mitochondrial DNA HVS-I and HVS-II in Chinese Bai ethnic group.

For forensic and population genetic purposes, a total of 125 unrelated volunteers' blood samples were collected from Chinese Bai ethnic minority group to analyze sequence variation of two hypervariable segments (HVS-I and HVS-II) in the mitochondrial DNA control region. Comparing the HVS-I and HVS-II sequences of the 125 Chinese Bais to the Anderson reference sequence, we found 86 polymorphic loci in HVS-I and 40 in HVS-II in mitochondrial DNA sequences of the Chinese Bai ethnic minority group, which defined 93 and 53 different haplotypes, respectively. Haplotype diversity and the mean pairwise differences were 0.992 ± 0.003 and 6.553 in HVS-I, and 0.877 ± 0.027 and 2.407 in HVS-II, respectively. We defined four macrohaplogroups R, M, N and D with the proportions ranging from 9.6% to 40.0%. With the analysis of the hypervariable domain from nucleotide 16 180-16 193 in HVS-I, our study revealed new haplotypes of sequence variations. In addition, the Fst metric, phylogenetic tree, and principal component analysis demonstrated a close genetic relationship between the Bai group and Chinese Han populations from South China, Changsha, and Guangdong. The results support that the Bai group is a multiorigin ethnic minority that has merged with the Chinese Han population.

Developmental validation of the AGCU 21+1 STR kit: a novel multiplex assay for forensic application.

In this study, we describe the developmental validation assay performed on a novel designed STR multiplex system, AGCU 21+1 STR kit. This kit contains a sex-determining locus amelogenin and 21 noncombined DNA index system STR loci, that are, D6S474, D12ATA63, D22S1045, D10S1248, D1S1677, D11S4463, D1S1627, D3S4529, D2S441, D6S1017, D4S2408, D19S433, D17S1301, D1GATA113, D18S853, D20S482, D14S1434, D9S1122, D2S1776, D10S1435, and D5S2500. The 21+1 kit was validated by a series of tests including optimized PCR conditions, sensitivity, precision and accuracy, stutter ratio, DNA mixture, inhibitors, and species specificity according to the revised validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Our results in this study show that the kit is a useful tool for forensic application.