云南怒族X染色体5个STR基因座遗传多态性

目的以云南怒族无关个体为研究对象,调查怒族群体DXS6804、DXS6799、DXS8378、DXS7130、DXS7132基因座的基因频率及基因型频率分布,建立群体遗传数据库。方法用聚合酶链反应(PCR)、变性聚丙烯酰胺凝胶电泳结合银染的方法,检测100名云南怒族个体X染色体上5个STR基因座的重复序列长度变化。结果云南怒族群体5个STR基因座具有遗传多态性,χ2检验表明多态性分布符合Hardy-Weinberg平衡定律。结论云南怒族群体DXS6804、DXS6799、DXS8378、DXS7130和DXS7132基因座,可用于法医学个体识别、亲子鉴定等研究。     

The Karimojong from Uganda: Genetic characterization using an X-STR decaplex system

The Karimojong, an African group from the Karamoja region of Northeast Uganda, were genetically analysed using a decaplex system for X chromosome short tandem repeats (X-STRs). A total of 255 individuals (117 males and 138 females) were genotyped for the following loci: DXS8378, DXS9898, DXS7133, GATA31E08, GATA172D05, DXS7423, DXS6809, DXS7132, DXS9902 and DXS6789. Allele frequencies and parameters for forensic evaluation were calculated for each STR. No association was found between any pairs of loci studied. DXS6789 was the most polymorphic marker in this sample, followed by DXS6809, with gene diversities of 84.79% and 83.94%, respectively. The less discriminating locus observed was DXS7133, with a gene diversity of 39.79%. High overall values of power of discrimination were obtained for female (1 in 1.8 × 10¹⁰) and male samples (1 in 1.6 × 10⁶), as well as high power of exclusion in father/mother/daughter trios (99.9997%), in father daughter duos (99.9862%) and in half sisters with same father (99.0331%). These results confirm the potential of this 10-plex in parentage testing and in human identification.     

Development of a heptaplex PCR system to analyse X-chromosome STR loci from five Italian population samples. A collaborative study

Many X-chromosome short tandem repeats (X-STRs) have been validated for forensic use even if further studies are needed on allele frequencies and mutation rates to evaluate the extent of polymorphism in different populations and to establish reference databases useful for forensic applications and for anthropological studies. A single multiplex reaction of seven X-STRs, which includes the DXS6789, HUMARA, DXS10011, DXS7423, HPRTB, DXS6807, DXS101 loci, is presented and their allele frequency distribution in a large population sample including 556 subjects (268 females and 288 males) analysed by five forensic laboratories of Central and Northern Italy is shown. Our results demonstrate the feasibility of a single amplification/detection reaction involving seven markers of the X chromosome, which can be fruitfully used in complex kinship analysis.     

Sequence variation at three X chromosomal short tandem repeats in Caucasian and African populations

Sequence variation for the X chromosome short tandem repeats (X-STRs) DXS9898, DXS6789 and GATA172D05 was studied in two major population groups, namely Caucasians and Africans. DXS6789 revealed two different subtype sequence polymorphisms: for shorter alleles, with less than 17 repeats, results showed a simple composition with the following structure: (TATG)_m-(TATC)_n. For longer alleles, a constant TATC insertion was observed at the beginning of the variable repeat unit. Additionally, alleles identical in size revealed structural variations regarding the TATG/TATC proportion. Africans showed a higher intra-allelic variation at this locus than the Caucasian population group. For all three loci, DXS9898, DXS6789 and GATA172D05, no unique structure was found among Africans and Caucasians.     

Optimization and validation studies of the Mentype Argus X-8 kit for paternity cases

The use of ChrX-STRs is enormous in forensic case as these have proven to be powerful tools, mainly in deficiency paternity cases when the disputed child is female, and also some special cases involving blood relatives, incest cases, fetal typing in abortion material. The Mentype^® Argus X-8 kit is a commercial multiplex system which contains Amelogenin for gender determination as well as gonosomal STR markers (DXS8378, HPRTB, DXS7423, DXS7132, DXS10134, DXS10074, DXS10101 and DXS10135). Validation studies were being performed on blood obtained from the volunteers in Turkish population. In this study, some parameters were taken under consideration for validation like DNA extraction using different protocols, quantitated by using commercially available Invitrogen Qubit Fluorometer, reaction volume validation of Master Mix and the analysis of female/male, female/female and male/male mixtures were performed. The conditions were optimized and validated using GenAmp 9700 and reducing reaction volume from 25 μl to 12.5 μl and 6.5 μl. After reducing the total volume of the reaction, the results were same and there was no effect on peak height and quality when analyzed on ABI 310 genetic analyzer. 2 paternity cases were also performed which gave the same power of discrimination as has been mentioned in Mentype^® Argus X-8 kit.     

Population genetic data of five X-chromosomal loci in Bauru (São Paulo, Brazil)

Genetic population data for five X-STR (DXS6854, DXS7424, DXS101, DXS6808 and DXS7132) were obtained from Bauru population (São Paulo, Brazil). No deviations from the Hardy-Weinberg equilibrium were observed, with the exception of DXS101. The combined powers of discrimination in males and females were 0.99897253 and 0.99999120, respectively. These high values show the potential of this system in human identification and paternity testing.     

西安汉族X染色体上6个STR位点的遗传多态性

目的调查西安汉族人群6个位于X染色体上的短串联重复序列:DXS8378、DXS7132、DXS6789、DXS101、HPRTB和DXS7423的基因及基因型频率分布。方法应用PCR和变性聚丙烯酰胺凝胶电泳及银染技术检测结果。结果在120例女性无关个体中,DXS8378、DXS7132、DXS6789、DXS101、HPRTB和DXS7423分别检出5、6、11、10、8和4个等位基因;分别检出10、17、29、32、22和7种基因型;此6个位点女性的基因型频率分布均符合Hardy-Weinberg平衡。结论此6个X染色体STR位点均有较高的个体识别率,在个体识别和女孩的亲权鉴定中有应用价值,对疾病相关研究有实际意义。     

Genetic characterization of an X-STR decaplex on the population of Pichincha (Ecuador)

This study reports data of ten X-STR markers (DXS8378; GATA172D05; DXS6809; DXS7132, GATA31E08, DXS9898, DXS7133, DXS7423, DXS9902, DXS6789) in Ecuadorian population from Pichincha (Sierra Region). To achieve these, we selected 100 non-related individuals that had signed informed consent (48 women and 52 men). They were typified using markers previously described by the Spanish and Portuguese ISFG Working Group (GEP-ISFG, 2008) and following their experimental recommendations.     

Analysis of 8 STR of the X-chromosome in two Italian regions (Umbria and Sardinia)

Eight X-chromosome STR were investigated in two groups of individuals from two Italian regions, Umbria and Sardinia. These two regions have a very different history. Umbria, situated in the centre of Italy and without defensive natural barriers, in the course of the centuries has been object of many invasions and appropriations by foreign people. On the contrary, Sardinia, an island in the centre of the Mediterranean sea, has endured a minor number of foreign invasions. The ChrX markers were amplified in a pentaplex (DXS6789, DXS7423, DXS6807, DXS101, DXS8377) and a triplex (DXS10074, DXS10075, DXS10079) that represents a haplotype. The DNA was extracted from 200 blood samples using the QIAmp DNA Minikit (Qiagen™). Amplification products were detected on an ABI PRISM 310 Genetic Analyzer (Applied Biosystems), using the same dye labels, run conditions, standard (GeneScan 500 Liz) and matrix file of AmpFlSTRIdentifiler. Statistical analyses for all the loci and intergroup comparisons between the two regional groups of individuals were performed.     

Population data for six X-chromosome STR loci in a Rio de Janeiro (Brazil) sample: Usefulness in forensic casework

This study presents data for the X-chromosome STR loci DXS7133, DXS7424, DXS8378, DXS6807, DXS7423 and DXS8377. In order to establish a database, unrelated individuals (males and females) from Rio de Janeiro were typed for the above loci. No significant differences were observed between allele frequencies in male and female samples (non-differentiation exact P values ≥ 0.156). Hardy-Weinberg equilibrium was tested in the female sample and no significant deviations were found. All six markers have shown to be highly polymorphic in our sample with gene diversities varying between 0.6797 for DXS7133, and 0.9260 for DXS8377. Pairwise linkage disequilibrium analysis did not allow discharging a possible association between DXS7133 and DXS7424 alleles in Rio de Janeiro population. Parameters of forensic interest, like PD_M, PD_F, Het_obs, Het_exp, were calculated for each locus. The high discrimination power estimated in both males and females, as well as mean exclusion chance in father/daughter duos and in father/mother/daughter trios, demonstrates the usefulness of these six markers in forensic investigation.     

Genetic Polymorphisms of four X-STR Loci: DXS6797, DXS6800, HPRTB and GATA172D05 in a Peruvian population sample

The X linked short tandem repeats (STR) markers have proven to be very useful tools for paternity testing when the disputed child is female. The purpose of this study was to describe the genetic polymorphism of four X-chromosomal STR loci (DXS6797, DXS6800, HPRTB and GATA172D05) in a Peruvian population sample and evaluate their efficiency in forensic practice and paternity testing.     

Polymorphism of eight X-chromosomal STRs in a Japanese population

Eight X-chromosomal short tandem repeat (X-STR) markers were analyzed in 258 unrelated Japanese (144 males and 114 females) using Mentype^® Argus X-8 PCR Amplification Kit (Biotype AG) which contains DXS7132, DXS7423, DXS8378, DXS10074, DXS10101, DXS10134, DXS10135 and HPRTB. The DXS10135 locus proved to be highly polymorphic marker (PIC: 0.945) and the DXS7423 showed the lowest value (PIC: 0.453). The exact test for genotype distribution showed no significant deviation from the Hardy-Weinberg equilibrium.     

Population data for 8 X-chromosome STR loci in a population sample from Northern Italy and from the Sardinia island

To establish a database for DXS8378, HPRTB, DXS7423, DXS7132, DXS10134, DXS10074, DXS10101, DXS10135 loci in an Italian population sample from Brescia (Northern Italy) and from the Sardinia island, 131 unrelated individuals were typed. DNA was amplified in a multiplex reaction with subsequent automatic detection using capillary electrophoresis. The obtained data give a contribution to the definition of Italian population STR allele frequencies for the eight analysed loci.     

Development of the X-linked tetrameric microsatellite markers HumDXS6803 and HumDXS9895 for forensic purpose

This paper presents sequence and population genetic data of the X-linked DXS6803 and DXS9895 short tandem repeat (STR). The tetranucleotide repeat polymorphism DXS6803 (also known as CHLC.GATA45H11) and DXS9895 (also known as CHLC.GATA124B04) are located at the Xq12-Xq21.33 and Xpter-Xp22.2 region, respectively. In kinship testing, DXS6803 and DXS9895 are suitable for concomitant use. Population genetic data were obtained by analyzing 182 unrelated females and 110 males from Chinese Han population. In this population, both DXS6803 and DXS9895 exhibited seven clearly distinguishable alleles ranging from 109bp to 128bp and 139bp to 163bp in length, respectively. Testing for Hardy-Weinberg equilibrium (HWE) showed no significant deviation for these two loci. The polymorphism information content (PIC), observed heterozygosity (H(obs)) and power of exclusion for parentage testing of a girl for trios (PE(trio)) and duos (PE(duo)) were 0.67, 0.687, 0.673 and 0.530 for DXS6803, and 0.69, 0.736, 0.688 and 0.547 for DXS9895, respectively. Seventy-eight families studies of these two loci confirmed X-linked codominant inheritance and mutations were not found.     

Development of the X-linked tetrameric microsatellite marker HumDXS6789 for forensic purposes

This paper presents sequence and population genetic data of the X-linked DXS6789 short tandem repeat (STR). The tetranucleotide repeat polymorphism DXS6789, also known as CHLC.GATA31F01, is located at the Xq22.3 region. This locus is unlinked with DXS6807 and slightly linked with ARA, DXS9898 and HPRTB. In kinship testing, DXS6789 is suitable for concomitant use with DXS6807. Population genetic data were obtained by analysing 250 unrelated males and 315 females from East Germany. In this population, the STR exhibited 12 clearly distinguishable alleles ranging from 154 to 198bps in length. DXS6789 is characterised by the following data: polymorphic information content (PIC)=0.70; observed heterozygosity (Het)=0.78; mean exclusion chance (MEC)=0.70. A deviation from the Hardy-Weinberg equilibrium could not be detected. The investigations we performed in 243 mother-child and 161 father-child meioses did not reveal any mutations.     

广东汉族群体DXS6854基因座的多态性

目的调查X染色体特异性基因座DXS6854在广东汉族群体的多态性。方法利用PCR和聚丙烯酰胺凝胶电泳及银染法显色技术进行基因分型。结果在广东汉族189名无关女性个体及230名无关男性个体中,发现了8个等位基因。等位基因频率分布在0.0026—0.4522之间,女性的基因型分布符合Hardy—Weinberg平衡,女性和男性个体的个体识别率(DP)分别为0.8633和0.7012。三联体检验非父排除率(PE)为0.6712。结论DXS6854有较高的个体识别率和亲权排除率,在个人识别和女孩的亲权鉴定中有应用价值。     

Validation of the STR DXS7424 and the linkage situation on the X-chromosome

X-linked microsatellite markers have proven to be powerful tools for parentage testing, mainly in deficiency paternity cases when the disputed child is female. However, only a small number of X-linked short tandem repeats (STRs) have been comprehensively described for forensic applications to date.We present sequence and population genetic data of the DXS7424 STR (GDB-G00-577-633) which is a trinucleotide repeat polymorphism representing 12 alleles of 147-180 bp in length. DXS7424 is located at Xq22 and closely linked to DXS101, corresponding to a genetic localisation of 104.9-121 cM from Xp-tel.PCR fragment length measurements and sequencing were carried out using the automatic gene analyser ABI 310 (Applied Biosystems).The population of 764 unrelated Germans checked for this STR exhibited the following features: polymorphism information content (PIC) = 0.780; heterozygosity (Het) = 0.843; mean exclusion chance (MEC = 0.766. Kinship tests revealed a typical X-linked inheritance. In 300 meioses under investigation, mutations were not found. Significant deviations from the Hardy-Weinberg equilibrium (HWE) were not established.Linkage studies confirmed closely linkage to DXS101. Additional we found linkage disequilibrium between DXS7424 and DXS101. This requires to use the established haplotype frequencies in kinship testing.     

Genetic data of 10 X-STRs in a population sample from Lima,Perú

Genetic population data for 10 X-STR (DXS6789, DXS9902, DXS7132, GATA31E08, DXS7133, DXS9898, DXS8378, DXS6809, DXS7423 and GATA172D05) were obtained from Lima population. The present study results support the usefulness of these markers in kinship investigation and also in population genetics studies.     

浙江汉族人群12个X-STR基因座遗传多态性调查

目的调查12个X染色体STR基因座在浙江汉族人群的遗传多态性,为法医学应用提供基础数据。方法应用ZJGA-X12荧光标记复合扩增系统,对浙江汉族468名无关男性个体与449名无关女性个体进行DXS7133、DXS8378、DXS981、DXS7424、DXS6789、DXS10159、GATA165B12、DXS101、DXS7423、GA-TA31E08、DXS10164、DXS10162这12个X-STR基因座的复合扩增,用ABI3130XL型基因分析仪对扩增产物进行检测,并统计这12个X-STR基因座的群体遗传学参数。结果获得12个X-STR基因座的等位基因频率分布,分别检出8、7、13、12、11、8、7、16、6、8、9、11个等位基因,获得男性样本DXS10159-DXS10162-DXS10164与DXS101-DXS7424两组连锁基因座单倍型119、62种;分别统计了12个X-STR基因座的GD、DP、MEC等法医遗传学参数。结论 12个X-STR基因座具有较强个体识别能力,可应用于法庭科学中的个体识别与亲权鉴定。     

Allele distribution of three X-chromosome STR loci in an antioquian population sample

The X-linked short tandem repeats (STR) markers have proven to be very useful tools for paternity testing when the disputed child is female. The aim of this study was to describe the polymorphism of three X-chromosomal STR loci (DXS6797, DXS6800 and HPRTB) in an Antioquian (Colombian) population sample. PCR products were separated in 4% acrylamide-bis-acrylamide denaturing gels followed by silver staining. Allele size determination and genotyping were performed according to recommendations of the DNA Commission of the International Society of Forensic Genetic using the allelic ladder manufactured at home and based on DNA controls including K562 and 9947A (Promega). Gene frequencies were calculated using ARLEQUIN version 3.11. Population genetic data were obtained by analyzing 127-400 unrelated males and 135 unrelated females from Antioquian (Colombian) population. Distribution of the allele frequencies of these systems for Antioquia population is similar to the European populations.