Power Of Discrimination In Females Research Articles

Forensic autosomal and gonosomal short tandem repeat marker reference database for populations in Burkina Faso

Tandem repeat genetic profiles used in forensic applications varies between populations. Despite the diversity and security issues in the Sahel that require the identification of victims (soldiers and civilians), Burkina Faso (BF) remains understudied. To fill this information gap, 396 unrelated individuals from BF were genotyped using a MICROREADER 21 ID System kit. All 20 short tandem repeat (STR) loci tested passed the Hardy–Weinberg equilibrium (HWE) test. The combined powers of exclusion for duos (CPE duos) and trios (CPE trios) for the 20 tested loci were 0.9999998 and 0.9999307, respectively. The probability that two individuals would share the same DNA profiles among the BF population was 9.80898 × 10–26. For the X-chromosome STR analysis, 292 individuals were included in this study using a MICROREADER 19X Direct ID System kit. Among the 19 loci, no significant deviations from HWE test were observed in female samples after Bonferroni correction (p < 0.05/19 = 0.0026), except for loci GATA165B12 and DXS7423. The results showed that the combined power of exclusion (CPE) and the combined power of discrimination in females (CPDF) and males (CPDM) were 0.999999760893, 0.999999999992, and 1, respectively. Comparison with other African sub-populations showed that geographical proximity is a reliable indicator of genetic relatedness.

X-chromosomal STRs for genetic composition analysis of Guizhou Dong group and its phylogenetic relationships with other reference populations

Background X-chromosomes show a specific genetic mode, which makes genetic markers on the X-chromosome play crucial roles in forensic research and human evolution. Dong group, one of 55 minority groups in China, live in Guizhou, Guangxi, and Hunan provinces. Even though some genetic data of Y chromosomal short tandem repeats (STRs) and autosomal insertion/deletion polymorphism (InDels) in Dong groups have been reported, there is little research about X-STRs in the Dong group. Aim Purposes of this study are to investigate allelic distributions and forensic statistical parameters of 19 X-STRs in the Guizhou Dong group, and explore the genetic composition of the Guizhou Dong group and its phylogenetic relationships with other reference populations. Subjects and methods Five hundred and seven Dongs (272 males and 235 females) living in Guizhou province were typed using the AGCU X19 STR kit. Allelic frequencies and forensic parameters of 19 X-STRs in the Guizhou Dong group were calculated. Population genetic analyses of Guizhou Dong and another 17 reference populations were conducted using DA genetic distances, phylogenetic tree, principal component analysis, and multidimensional scaling. Results A total of 230 alleles of 19 X-STRs were identified in all Dongs. The frequencies of 19 loci ranged from 0.0013 to 0.6838. The values for cumulative power of discrimination in males (PDM), cumulative power of discrimination in females (PDF), and four different kinds of mean exclusion chance (MEC_Kruger, MEC_Kishida, MEC_Desmarais, and MEC_Desmarais_du) for the 19 X-STRs in all individuals were 0.999999999999761, 0.9999999999999999999993951, 0.999999964841617, 0.999999999997261, 0.999999999997297, and 0.999999993623172, respectively. Besides, genetic polymorphisms of seven linkage clusters ranged from 0.9381 to 0.9963. In addition, these seven groups showed high polymorphism information content (PIC), PDM, PDF, MEC_Kruger, MEC_Kishida, MEC_Desmarais, and MEC_Desmarais_duo. Population genetic analyses of Guizhou Dong and another 17 reference populations showed that the Guizhou Dong group had close genetic relationships with surrounding Tai–Kadai-speaking, Hmong-Mien-speaking, and Han groups. Conclusion Nineteen X-STRs displayed high genetic diversities and could be employed for forensic personal identification and paternity analysis in the Guizhou Dong group. Close genetic affinities between Guizhou Dong and surrounding populations were observed based on the 19 X-STRs in 17 reference populations.

Genetic polymorphisms of 16 X-STR loci in the Hani population from Southwest China

X chromosomal short tandem repeats (X-STRs) have the characteristics of both autosomal and uniparental genetic markers and have been shown to be particularly useful in forensic casework. However, relevant research or reports have not focused on X-STRs in the Hani population. To investigate the genetic variation and forensic efficiency of 16 X-STR loci in the Hani ethnic minority, we calculated the allele frequencies and forensic parameters of 451 (116 males and 335 females) unrelated healthy Hani individuals from Yunnan Province, Southwest China. All these loci are highly polymorphic in Hani individuals in Yunnan Province except DXS6800. The combined power of discrimination in males (PDM) and power of discrimination in females (PDF) were found to be 0.999 999 998 433 993 and 0.999 999 999 999 998, respectively. Furthermore, a population genetic structure investigation between the Yunnan Hani population and another 18 populations was performed using a principal component analysis, multidimensional scaling plot and neighbouring-joining phylogenetic tree and the findings illustrated that neighbouring populations and different nationalities in the same area appeared to have a closer evolutionary relationship. This study provides the first batch of X chromosome genetic polymorphism data of the Hani population in Yunnan Province, Southwest China and enriches the reference database of the Chinese minority population. Key points This is the first study of X-STR in the Hani population. We calculated the allele frequencies and forensic parameters of 451 unrelated healthy Hani individuals from Yunnan Province, Southwest China. All these loci are highly polymorphic in Hani individuals in Yunnan Province except DXS6800. The genetic relationship between the Hani and the other 18 nationalities was analyzed. This study provides the first batch of X chromosome genetic polymorphism data of the Hani population in Yunnan Province, Southwest China and enriches the reference database of the Chinese minority population.

Genetic polymorphism investigation of 16 X-STR loci in the Bai ethnic minority in Yunnan Province, Southwest China.

To investigate the genetic variation and forensic efficiency of 16 X-chromosomal short tandem repeat (X-STR) loci (DX6795, DXS9902, DXS8378, HPRTB, GATA165B12, DXS7132, DXS7424, DXS6807, DXS6803, GATA172D05, DXS6800, DXS10134, GATA31E08, DXS10159, DXS6789, and DXS6810) in the Bai minority, we calculated allele frequencies, forensic parameters, and haplotype frequencies in 424 (202 males and 222 females) unrelated, healthy Bai individuals from Dali Bai Autonomous Prefecture in Yunnan Province, China. We observed a total of 132 alleles; 5-19 alleles were detected in each locus, and the corresponding allele frequencies ranged from 0.0016 to 0.7589. All of the loci detected were highly polymorphic in the Bai population in Yunnan Province, except DXS6800. The values for the combined power of discrimination in females (PDf) and males (PDm) were 0.999999999999996 and 0.999999997487061, respectively. According to a phylogenetic tree, neighboring populations and different nationalities in the same area appeared to have relatively close evolutionary relationships. This study provides and complements X-chromosome genetic polymorphism data for the Bai people in Yunnan Province, Southwest China, and enriches the available reference materials for this Chinese minority population.

Genetic analysis of 12 X-short tandem repeats loci in a northern Thai population.

Short tandem repeats (STRs) are widely used as DNA markers in paternity testing and criminal investigations because of their high genetic polymorphism among individuals in population. However, many factors influence genetic variations of STRs. Therefore, understanding STR information within individual populations could provide database and scientifically reliable STR genotyping for forensic genetic purposes. We aimed to examine allele frequencies of X-STRs, including some forensic parameters, in a northern Thai population. A retrospective descriptive study was conducted by collecting X-STR data from unrelated individuals living in a northern region of Thailand. The allele frequency and forensic parameters - for example polymorphism information content (PIC), power of discrimination in females and males (PDf and PDm), mean exclusion chance (MEC) and haplotype frequency - were calculated. The Hardy-Weinberg equilibrium was analysed. A total of 132 alleles were observed, with corresponding allele frequency ranging from 0.0064 to 0.4904. The PIC of all loci was >0.6, representing high genetic polymorphism, except DXS8378 and DXS7423. Notably, DXS10135 was the most diverse loci with the highest PD and MEC, while DXS7423 was the least polymorphic marker with the lowest PD and MEC. The highest haplotype diversity in male data was on linkage group III (DXS10101-DXS10103-HPRTB) by 0.9895. The genetic distance analysis demonstrated that the northern Thai population had a close relationship with Taiwanese (DA = 0.023). There are no significant deviations among the Hardy-Weinberg equilibrium except DXS10148. This study has established a northern Thai X-STRs reference database to be used as a tool for forensic genetic purposes.

Genetic diversity of X-STR markers in Jat Sikh population of Punjab, India and its comparison with other 39 global populations

Background The Jat Sikh population is the largest endogamous group of Punjab, a state in north-west India, and has not yet been explored for genetic polymorphism based on X-STR genetic markers. In India, which is the second most populous country in the world, only two population studies based on X-STR markers have been reported so far. Aim To explore the genetic diversity of 12 X chromosomal STR genetic markers in the Jat Sikh population of Punjab and expand the X-STR polymorphism database. Subjects and methods In this study, a total of 200 Jat Sikh individuals (100 males and 100 females) residing in Punjab were investigated for 12 X-STR markers using the Investigator Argus X-12 QS Kit. Results The highest power of discrimination (PD) in females (PDf) and males (PDm) was observed to be 0.965 (DXS10135) and 0.929 (DXS10135 and DXS10148), respectively. DXS10135 was found to be the most polymorphic and discriminating locus among all the studied loci in both males and females with highest values of power of discrimination (PD) and polymorphic information content (PIC) as well. Conclusion Overall, the studied markers of the Argus 12 X-STR kit provide high polymorphic information which may prove to be an important tool in resolving issues such as missing person identification, incest, immigration disputes, kinship analysis and genealogical studies. The dataset obtained from this study will add to the present database of X-STRs.

Genetic polymorphism analyses of three novel X chromosomal short tandem repeat loci in the Xp22.3 region.

X chromosomal short tandem repeats (X-STRs) can be useful for haplotype analysis in DNA testing, particularly for complex kinship testing or when one parent is absent. We searched downstream of four previously detected loci in the Xp22.3 region (LC149476, LC149479, LC149480, and LC149484) and detected and analyzed three novel short tandem repeats (STRs), LC317283, LC317284, and LC317285, with the repeat sequences TATAA, TTTA, and TATC, respectively. The forensic statistical values in Japanese subjects were confirmed to be noninferior to existing loci, with values for polymorphism information content, the power of discrimination in males (PDm), and the power of discrimination in females (PDf) of 0.5606-0.7448, 0.6078-0.7774, and 0.7990-0.9178, respectively. Haplotype analysis also revealed linkage disequilibrium between LC317283 and the four known loci (LC149476, LC149479, LC149480, and LC149484) and between two other novel loci (LC317284 and LC317285). Analysis of three family samples suggested that these STRs could be useful in complex kinship testing, so we developed an X-STR multiplex polymerase chain reaction (PCR) system for the seven loci and confirmed its ability to provide favorable amplification. We anticipate that the identified loci and developed multiplex PCR system will be beneficial to the field of forensic medicine.

X-chromosomal STR-based genetic structure of Sichuan Tibetan minority ethnicity group and its relationships to various groups.

The X-chromosomal short tandem repeats (STRs) with more informative than autosomal STRs in some complicated biological relationships identification due to its specific mode of genetic transmission can be used as a complementary tool in forensic case practices. In this study, we presented the population genetic data of 19 X-STRs, consisting of DXS10174, DXS10075, DXS10079, DXS101, DXS10101, DXS10103, DXS10134, DXS10135, DXS10148, DXS10159, DXS10162, DXS10164, DXS6789, DXS6809, DXS7132, DXS7423, DXS7424, DXS8378, and HPRTB loci, in a sample of 235 individuals of Tibetan nationality from Sichuan province, Southwest China. All 19 X-STR loci were consistent with Hardy-Weinberg equilibrium. The results showed that the combined power of discrimination in females and males are 0.999999999999999999997 and 0.9999999999997, respectively. In addition, the mean paternity exclusion chances based on the formula of MECKrüger, MECKishida, and MECDesmarais as well as MECDesmarais Duo are 0.99999991, 0.9999999999924, 0.9999999999929, and 0.999999985, respectively. In summary, our findings suggested that the AGCU X19 kit can be considered to serve as a high polymorphic information tool for forensic identification and kinship testing in the Sichuan Tibetan population. Furthermore, population genetic structure investigation between Sichuan Tibetan population and other 19 populations using PCA, MDS, and phylogenetic tree illustrated that significant genetic difference was observed between the Sichuan Tibetan and Malay, as well as the Xinjiang Uyghur population.

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.

Forensic efficiency parameters of the Investigator Argus X-12 kit in women from two Mestizo and seven Amerindian populations from Mexico

Allele frequency distribution and statistical parameters of forensic efficiency concerning the Investigator Argus X-12 kit (Qiagen, Hilden, Germany) were determined in a total sample of 641 unrelated Mexican females, including two Mestizo-admixed- populations (n=309) and seven Amerindian groups (n=332) from the main regions of the country. Most of the 12 X-STRs were in agreement with Hardy-Weinberg expectations in all nine Mexican populations. The power of discrimination in females (PD) and Median exclusion chance for trios (MECT) and duos (MECD) of this genetic system based on X-STRs were >99.99%. Although Mexican populations showed significant pairwise differentiation, a closer relationship was evident between Amerindian groups and nearby Mestizos, in agreement with historical records, previous genetic studies, and X-linked inheritance pattern expectations.

Analysis of four novel X-chromosomal short tandem repeats within 71kb of the Xp22.3 region.

DNA testing using X-chromosomal short tandem repeat (X-STR) polymorphisms has been used in maternity/paternity and complex kinship cases. Analyses of repeat sequences, surveys on racial statistics, and development of practical applications for DNA testing continue to be reported. In this study, we identified four novel tetranucleotide STR loci located in the X chromosome, which is the basis of X-STR research. These four tetranucleotide STRs were located within 71kb of the chromosome Xp22.3 region. Using sequence analysis of the structure of repeat sequences, we identified simple repeat sequences of TAAA, CTTT, TATC, and GATA with rare insertions. We then calculated forensic statistical parameters using base length analysis. In the Japanese population, the polymorphism information content was 0.597-0.687, power of discrimination in females was 0.829-0.884, and power of discrimination in males was 0.635-0.729. As these tetranucleotide STRs are closely linked, we conducted haplotype analysis and detected that three loci (LC149476, LC149479, and LC149480) were in linkage disequilibrium. We demonstrated that the simultaneous analysis of these loci may be useful in complex kinship cases. Because these four loci can be detected by multiplex PCR, the detection of alleles at these loci can be rapidly and easily achieved. We conclude that the X-STR loci detected in this study may be useful tools in complex kinship cases and may increase the reliability of genetic testing.

Genetic diversity and haplotypic structure of Chinese Kazak ethnic group revealed by 19 STRs on the X chromosome

X-chromosomal short tandem repeats (X-STRs) have been widely used in forensic practices involving complicated ties of kinship over the past years, and also play an increasingly important role in population genetics. To study the genetic polymorphisms of 19 STR loci on X chromosome in Chinese Kazak ethnic group, we investigated the allelic and haplotypic frequencies of the 19 loci in 300 (149 males and 151 females) unrelated healthy individuals from Ili Kazak Autonomous Prefecture, Xinjiang Uigur Autonomous Region of China after having evaluated the forensic application value of these loci in forensic sciences, and then compared the population distinctions between the Kazak group and other reference groups. We observed a total of 240 alleles at these X-STR loci with the corresponding allelic frequencies ranging from 0.0017 to 0.5917. In the study, the highest polymorphism was found at DXS10135 locus. The combined power of discrimination in females was 0.999999999999999999999985 and in males 0.999999999999968. The present study indicates that the 19 X-STR loci are very useful for both forensic identification cases and kinship analyses involving a female offspring.

Genetic polymorphism analyses of a novel panel of 19 X-STR loci in the Chinese Uygur ethnic minority.

The population genetic data and forensic parameters of 19 X-chromosome short tandem repeat (X-STR) loci in Chinese Uygur ethnic minority are presented. These loci were detected in a sample of 233 (94 males and 139 females) unrelated healthy individuals. We observed 238 alleles at the 19 X-STR loci, with the corresponding gene frequencies spanning the range from 0.0021 to 0.5644. After Bonferroni correction (P>0.0026), there were no significant deviations from Hardy-Weinberg equilibrium. The cumulative power of discrimination in females and males, and the probability of exclusion of the 19 X-STR loci were 0.999 999 999 999 999 999 998 091, 0.999 999 999 999 966, and 0.999 999 986 35, respectively. The cumulative mean exclusion chance was 0.999 999 992 849 in deficiency cases, 0.999 999 999 999 628 in normal trios, and 0.999 999 998 722 in duo cases. The high value of the forensic parameters mentioned above revealed that the novel panel of 19 loci had important values for forensic applications in the Uygur group.

Development of two multiplex PCR systems for the analysis of 14 X-chromosomal STR loci in a southern Brazilian population sample

We developed two multiplex systems for the coamplification of X-chromosomal short tandem repeats (STRs). X-Multiplex 1 consisted of DXS6807, DXS6800, DXS7424, DXS101, GATA172D05 and HPRTB and X-Multiplex 2 consisted of DXS8378, DXS9898, DXS6801, DXS6809, DXS6789, DXS7133, DXS8377 and DXS7423. In addition, we present allele frequencies for these loci in a south Brazilian population comprising 124 females and 141 males and haplotype frequencies of linked markers for males. Hardy-Weinberg equilibrium (HWE) was tested in the female sample and no significant deviations were found after applying Bonferroni's correction. Linkage disequilibrium (LD) tests were performed for all pairs of loci and three significant results, out of 91 pairwise comparisons, were obtained. We did not find any evidence of linkage disequilibrium between close or linked markers. The power of discrimination in females (PD(F)) varied between 0.832 for DXS6801 and 0.987 for DXS8377. DXS6801 was the least informative marker (PIC = 0.605), while DXS8377 was the most polymorphic (PIC = 0.911), followed by DXS101 (PIC = 0.872). Genetic distances were estimated for each STR marker applying the calculation of F (ST) between our total sample and other studies from Brazil, Europe, Asia and Africa. The most distant populations were Japan, Korea, China, Ghana and Uganda.

Development of the nine X-STR loci typing system and genetic analysis in three nationality populations from China

This study is to develop a new multiplex polymerase chain reaction (PCR) system that simultaneously amplifies the nine X-chromosome short tandem repeats loci in the same PCR reaction, and to explore their polymorphism and mutation rate among three nationality populations from China. These loci included DXS6854, DXS9902, DXS6809, GATA172D05, HPRTB, DXS7423, DXS6807, DXS8378, and DXS8377. The samples of 890 (484 males and 406 females) unrelated individuals from Guangdong Han population, Xinjiang Uigur, and Inner-Mongolia Mongol were successfully analyzed using this multiplex system. The allele frequencies and mutation rates of the nine loci were investigated, and the comparison of allele frequency distribution among different populations was performed. There were 87 alleles for all the loci, and six to 18 alleles for each locus observed by our new multiplex PCR system. Polymorphism information content was 0.4998-0.9101, and power of discrimination in females was 0.6518-0.9846. Five cases with mutation of above loci were detected in 5,310 meioses. Pair-wise comparisons of allele frequencies distribution showed significant differences for most loci among different populations. Our results indicate that this multiplex system is very useful for identification analysis, and that the information about polymorphism and mutation rate is necessary for forensic application in three nationality populations from China.

The establishment of a nine X-chromosome short tandem repeat loci multiplex PCR and detection of the polymorphism of these loci

To establish a nine X-chromosome short tandem repeats (X-STR) loci multiplex PCR method and study the polymorphism of the 9 X-STR loci,and to determine its application in kinship tests for forensic medicine. A fluorescent multiplex PCR that simultaneously amplifies 9 X-STR loci, i.e. DXS7133, DXS981, DXS7424, DXS6789, DXS7132, GATA165B12, DXS101, GATA31E08 and DXS10011, were set up. PCR products were analyzed using capillary electrophoresis and ABI prism 3100 Genetic Analyzer with GeneMapper ID 3.1 analysis software. When 251 unrelated male and 112 unrelated female individuals from southern China were tested, 111 alleles were detected. The power of discrimination in females was 0.5837-0.9959. Mean exclusion chance for X-STR in standard trios with daughters was 0.4072-0.9511. Polymorphism information content was 0.4481-0.9531. The results demonstrate that the 9 loci in the multiplex system provide high polymorphism information, and the multiplex system provides a fast technology for forensic identification and paternity testing. The X-STR multiplex system can complement the analysis of AS-STR and Y-STR efficiently.

An X-STR meiosis study in Kurds and Germans: allele frequencies and mutation rates

X-linked short tandem repeats (X-STRs) play an important supplementary role in the field of forensic genetics, especially in deficiency cases. This paper presents population genetic data for the microsatellite markers DXS8378, DXS6800, DXS101, HPRTB, and DXS8377 in a German and a Kurdish population sample. Buccal swabs were obtained from 217 unrelated healthy German individuals (107 women and 110 men) from the area of Münster and 208 unrelated Kurdish individuals (103 women and 105 men), immigrants mainly from Northern Iraq. Additionally, more than 1,200 meiotic transfers (419 paternal and 819 maternal meioses) were investigated in the systems DXS6800, DXS101, and DXS8377. Five mutations were found in the system DXS8377. With the power of discrimination in females [PD(F)] ranging from 0.81 (DXS8378 in Kurds) to 0.99 (DXS8377 in Germans), the investigated X-STRs systems turned out to be highly informative in the two populations.