Evaluation of Detection Efficiency for Trio Full Sibling Testing / 法医学杂志

OBJECTIVES@#To study the detection efficiency of trio full sibling with another known full sibling reference added under different number of autosomal STR typing systems.@*METHODS@#Based on 43 detection systems consisting of 13 to 55 representative autosomal STR loci, 10 000 true families (full sibling group) and 10 000 false families (unrelated individual group) were randomly simulated. The full sibling index (FSI) was calculated based on the method of family reconstruction. The cumulative sibling relationship index (CFSI) of 0.000 1 and 10 000 were used as the evaluation thresholds, and the detection efficiency parameters were calculated and compared with the identification of the duo full sibling testing.@*RESULTS@#With the increasing number of STR loci, the error rate and inability of judgement rate gradually decreased; the sensitivity, specificity, correct rate of judgment and other parameters gradually increased, and the system efficiency gradually improved. Under the same detection system, trio full sibling testing showed higher sensitivity, specificity, system efficiency and lower inability of judgement rate compared with duo full sibling testing. When the system efficiency was higher than 0.85 and inability of judgement rate was less than 0.01%, at least 20 STRs should be detected for trio full sibling testing, which was less than 29 STRs required by duo full sibling testing.@*CONCLUSIONS@#The detection efficiency of trio full sibling testing is superior to that of duo full sibling testing with the same detection system, which is an effective identification scheme for laboratories with inadequate detection systems or for materials with limited conditions.

Research Progresses of Tri-Allelic Patterns in Autosomal STR in Forensic DNA Analysis / 法医学杂志

Tri-allelic pattern in autosomal STR is a common abnormal typing phenomenon in forensic DNA analysis, which brings difficulties and uncertainties to the evaluation of the evidence weight in actual cases. This paper reviews the types, formation mechanism, occurrence frequency, genetic pattern and quantitative evaluation of evidence of the tri-allelic pattern in autosomal STR in forensic DNA analysis. This paper mainly explains the formation mechanism and genetic patterns based on different types of tri-allelic pattern. This paper also discusses the determination of tri-allelic pattern and the quantitative method of evidence evaluation in paternity testing and individual identification. This paper aims to provide references for scientific and standardized analysis of this abnormal typing phenomenon in forensic DNA analysis.

Analysis of Genetic Polymorphism and Population Genetic Structure of 57 Autosomal InDel Loci in Beichuan Qiang Population / 法医学杂志

OBJECTIVES@#To investigate the genetic information of 57 autosomal InDel loci (A-InDels) included in AGCU InDel 60 fluorescence detection kit in the Beichuan Qiang population of Sichuan Province and evaluate its application value in forensic medicine.@*METHODS@#A total of 200 unrelated healthy individuals from Beichuan Qiang population of Sichuan Province were typing detected by AGCU InDel 60 fluorescence detection kit. Allele frequencies and population genetic parameters of the 57 A-InDels were statistically analyzed and compared with the available data of 26 populations.@*RESULTS@#After Bonferroni correction, there was no linkage disequilibrium between the 57 A-InDels, and all loci were in Hardy-Weinberg equilibrium. Except for rs66595817 and rs72085595, the minor allele frequencies of 55 A-InDels were above 0.3. PIC ranged from 0.298 3 to 0.375 0, CDP was 1-2.974 8×10-24, CPEduo was 0.999 062 660, and CPEtrio was 0.999 999 999. The calculation of the genetic distance showed that Beichuan Qiang population had the closest genetic distances with Beijing Han and South China Han populations, but far away from African populations.@*CONCLUSIONS@#The 57 A-InDels in AGCU InDel 60 fluorescence detection kit have a good genetic polymorphism in Beichuan Qiang population of Sichuan Province, which can be used as effective supplemental for individual identification and paternity identification in forensic medicine.

Efficiency Analysis of Uncle-Nephew Relationship Identification by Increasing STR Markers and Adding Reference Samples / 法医学杂志

OBJECTIVES@#To estimate the system efficiency of uncle-nephew relationship identification by increasing STR markers and adding reference samples based on the test results of simulated data and real samples, so as to provide references for selecting the appropriate number of STRs and reference samples for uncle-nephew relationship identification.@*METHODS@#Five common models of uncle-nephew relationship identification were constructed by adding different reference samples. In each model, the likelihood ratio (LR) for 10 000 pairs of uncle-nephew relationships and 10 000 pairs of unrelated individuals were simulated by detecting 19, 39 or 55 STRs, and the system efficiency at different thresholds was simulated. The samples of the Han population in Zhejiang were collected, and 55 autosomal STRs were obtained by using SiFaSTRTM 23plex kit, Goldeneye® DNA ID 22NC kit and AGCU 21+1 PCR amplification kit. When 19, 39 and 55 STRs were detected, the LR of each model and system efficiency under different thresholds were calculated and compared with the simulation results.@*RESULTS@#Under the same detection system, the calculated results of simulated data and corresponding true samples were basically consistent. In the same model, there was a positive correlation between the system efficiency of uncle-nephew relationship identification and the number of STRs detected. Moreover, the system efficiency of introducing relatives was higher than identifying only two individuals. The order of preference for the introduction of relatives was the full sibling (or mother) of the uncle and the full sibling (or mother) of the nephew.@*CONCLUSIONS@#The system efficiency of uncle-nephew relationship identification could be improved by increasing the number of STRs and introducing known relatives, which would provide the basis for selecting the most appropriate detection system and reference individuals in actual cases.

Development and Forensic Application of EX20+30Y Kit / 法医学杂志

OBJECTIVES@#To develop a multiplex PCR amplification system (EX20+30Y for short) of 19 autosomes, 30 Y-STR loci plus the gender indicator, and evaluate its forensic application value.@*METHODS@#With the six-color fluorescence labeling technology, a multiplex amplification system of 19 autosomal STR loci and 30 Y-STR loci plus the gender indicator was constructed. Blood samples from 210 unrelated individuals, 69 daily case samples and standard samples 9948 and 9947A were collected for loci detection and analysis. The EX20+30Y multiplex amplification system was evaluated by its sensitivity, mixed sample detection ability, species specificity, balance, direct amplification ability, sample applicability and anti-inhibition ability.@*RESULTS@#Multiplex amplification of blood samples from 210 unrelated individuals by the detection system obtained accurate genotyping results. The detection sensitivity of standard samples was 0.125 ng and the species specificity was high. The 69 samples from daily cases were genotyped correctly. Moreover, standard sample 9948 could be accurately genotyped even if the samples contained a certain concentration of inhibitors.@*CONCLUSIONS@#The multiplex amplification system established in this study can conduct combined examination of 19 autosomes, 30 Y-STR loci plus the gender indicator with accurate genotyping and high sensitivity. It has a good forensic application prospect.

Polymorphisms of 19 Autosomal STR Loci in Sichuan Han Population and Their Forensic Application / 法医学杂志

Objective To investigate the allele distribution, population genetics parameters and genetic analysis of neighboring populations of 19 autosomal STR loci in Sichuan Han population, and to evaluate their forensic application value. Methods The Goldeneye?? DNA ID system 20A was used to perform multiplex PCR amplification and allelic gene typing of 19 STR loci in 1 201 unrelated Han individuals from Sichuan Province. Allele frequencies and population genetics parameters were calculated. The Nei's genetic distances between Sichuan Han population and 12 previously reported populations were analyzed. Multidimensional scaling and principal component analysis were carried out and phylogenetic trees were also constructed. Results The heterozygosity of 19 STR loci ranged from 0.617 0 to 0.915 1, their discrimination power ranged from 0.777 4 to 0.986 5, matching probability ranged from 0.013 5 to 0.222 6, polymorphism information content ranged from 0.546 4 to 0.910 5, probability of exclusion ranged from 0.311 8 to 0.826 3 （triplet） and from 0.197 9 to 0.712 1 （biplet）, and no significant deviations from Hardy-Weinberg equilibrium were observed. Based on the results of multidimensional scaling, principal component analysis and phylogenetic trees of the genetic distances between Sichuan Han population and the other 12 populations, Sichuan Han population was closest to Hubei Han population and was farthest to Xinjiang Uygur population. Conclusion The 19 autosomal STR loci showed a high polymorphism and discriminating ability in Sichuan Han population, which can provide a data foundation for personal identification, paternity test and population genetics study.

Calculation of Likelihood Ratio for Identifying Half Sibling Relationship When Both Biological Mothers Participate / 法医学杂志

Objective To derive the formulae for likelihood ratio （LR） calculation of half sibling relationships when both mothers participate. Methods Based on the fact that both biological mothers participate in the identification of half sibling relationship between the two individuals, test hypothesis for the identification of half sibling relationship was established. Conditional probability ratios of genetic evidence under null hypothesis and alternative hypothesis conditions were simplified, and then applied to a real case of half sibling relationship identification. At the same time, the LR of half sibling relationships under the assumption that only a single biological mother or none of the biological mothers participate were respectively calculated. Results In the cases of identification of half sibling relationship from same fathers, with no biological father involved, after the same genetic indicator test analysis, when both biological mothers participate in the identification, the accumulated LR value was higher than that of accumulated LR with only a single biological mother or no parents participating. Conclusion When the autosome STR test is used for the identification and analysis of half sibling relationship between two individuals, the calculation of LR is more simple, intuitive and operable with both mothers participating. The biological mothers should participate in the test as much as possible, otherwise the number of STR loci would need to be increased for a more specific conclusion.

Genetic Polymorphisms of 18 Autosomal STR loci in Changsha Han Population / 法医学杂志

OBJECTIVES@#To investigate the genetic polymorphisms of 18 autosomal short tandem repeats （STR） loci in Changsha Han population, and explore the population genetic relationships and evaluate its application value in forensic medicine.@*METHODS@#The DNA of 2 004 unrelated individuals in Changsha Han population were amplified using Goldeneye®DNA ID System BASIC, and the PCR products were analyzed by electrophoresis using 3130xl genetic analyzer. The fragment sizes of alleles were analyzed subsequently by GeneMapper® ID v3.2. The frequency data and forensic genetic parameters ［observed heterozygosity （Ho）, expected heterozygosity （He）, power of discrimination （DP） and polymorphic information content （PIC）］ of 18 STR loci were statistically analyzed. Total probability of discrimination （TDP）, probability of exclusion in trio cases （PEtrio） and probability of exclusion in duo cases （PEduo） were calculated by Cervus 3.0. Hardy-Weinberg equilibrium and linkage disequilibrium of the loci were detected by Arlequin v3.5. The results were compared with the available data of other populations from different races and regions.@*RESULTS@#The power of discrimination （DP）, and the polymorphic information content （PIC） of each locus of Changsha Han population ranged from 0.783 6 to 0.987 9 and 0.549 4 to 0.914 5, respectively. The TDP, cumulative probability of exclusion in trio cases （CPEtrio） and cumulative probability of exclusion in duo cases （CPEduo） were 0.999 999 999 999 999 999 999 865 2, 0.999 999 979 and 0.999 988 325, respectively. According to the Nei's DA genetic distance, the genetic distance between Changsha Han and Hunan Han populations was the smallest （0.014 1）, while it was the largest （0.041 8） between Changsha Han and Xinjiang Kazakh populations.@*CONCLUSIONS@#The 18 STR loci shows abundant genetic polymorphisms in Changsha Han population. The study of genetic diversity among different populations has an important meaning for the research of their origins, migrations and their relationships.

Study of polymorphisms in autosomal microsatellite loci among mongolian population / Монголын Анагаах Ухаан

IndroductionThe short tandem repeats (STR) are rich source of highly polymorphic markers in the human genome. In this study, we used a commercially available multiplex STR typing kit to study 15 STR systems (D3S1358, THO1, D21S11, D18S51, Penta E, D5S818, D13S317, D7S820, D16S539, CSF1PO, Penta D, vWA, D8S1179, TPOX and FGA,) in the Mongolians population, and estimated the allele and genotype frequencies. These 15 STR loci include 2 new pentanucleotide repeat STR loci, Penta E and Penta D, so are not studied in Mongolians.GoalTo determine allele frequency of STR loci D3S1358, THO1,D21S11, D18S51, D5S818, D13S317, D7S820, D16S539, CSF1PO, vWA, D8S1179, TPOX, FGA Penta E, Penta D in Mongolian population.Materials and MethodsThe liquid blood, blood stain and saliva samples were taken from 165 unrelated individuals from Mongolian. Extraction DNA: Genomic DNA was extracted from whole blood samples by the standard method of phenol-chloroform-isoamyl alcohol and Wizard Genomic DNA Purification kit, Promega Corporation [21], from blood stain and saliva samples QIAamp DNA micro kit, Qiagen [25], AccuPrep Genomic DNA Extration kit, Bioneer, Koreans extraction method respectively.PCR: PCR amplification was performed using 10-15 ng genomic DNA template according to manufacturer’s protocol (PowerPlex® 16 and PowerPlex® 16HS kit, Promega Corporation, USA). Typing: DNA typing was performed on the ABI Prism 310 Genetic Analyzer (Applied Biosystems) using the recommended protocol. The results were analyzed by Data Collection (Version 1.1), GeneScan (Version 3.1), and Genotyper (Version 3.1) softwares (AppliedBiosystems).ResultsWe assessed forensic and population genetic studies using 15 STR loci included in s sample of 165 unrelated individuals from Mongolian. Allele frequency were listed in Table 2. Totally 20 alleles /5, 7-25/ were found from microsatellite Penta E locus and allele 11 has most frequent (0.1128). 6-16 alleles were found from Penta D locus and allele 9 has most frequent (0.3262). This result is interesting because allele 6 of Penta D locus was found rarely among other populations. But relatively higher frequency of allele 6 (0.0183) was found in Mongolian population. A population comparison based in genetic distance and genetic diversity calculated from allele frequencies of the 15 STR loci from obtained five different populations is shown the Table 3. Conclusions:1. Penta E locus was highly polymorphic, and 20 alleles were found in this Mongolians population and allele 11 was most frequent.2. Penta D locus was 20 alleles were found in this Mongolians population and allele 9 was most frequent.

Research siblings identification by Identiffler system and automatic STR genetic / 中国法医学杂志

Objective To evaluate the probability of siblings identification in Identifiler system by using the software of automatic analysis.Methods Using the software of automatic analysis in siblings jdentification.STP genetic typing of 151 pairs of full siblings and 31224 pairs of unrelated individuals from manual simulation were analyzed in 15 STR loci of ldentifiler system.Results Kin probability(W_(FS))of 39.07% full siblings were more than 99.999% while W_(FS) of unrelated individual pairs were 0% .W_(FS) of 60.93% full siblings and 21.3% unrelated individual pairs were all at the range from 99.999% to 1% .W_(FS) of 78.7% unrelated individual pairs 0% full siblings individuals were less than 1% .Therefore,there were notability difference between full siblings and unrelated individual pairs.In addition,testing of 15 STR loci of Identifiler system,it suggested that the pair were siblings when the locus number of the entirely-same is not less than 5 or that of the entirely-different is not more than 1,and that the pair were unrelated individuals when the locus number of the entirely-different is not less than 6 or that of the entirely-8alne is not more than 1.Conclusion The software of automatic analysis and the Identifiler system call be used to siblings identification.

A Case of Male Infertility with a Reciprocal Translocation t(X;14)(p11.4;p12) / 대한진단검사의학회지

A chromosomal abnormality was found in about 3.6-7.6% of males presenting with azoospermia or oligospermia. Translocations between X chromosome and autosomes are rarely seen genetic disorders that cause male infertility. We described here a 26-year-old infertile male with t(X;14)(p11.4; p12). He showed a normal phenotype without any familial history of congenital abnormalities. The cytogenetic analysis of the proband revealed an X-autosomal translocation, 46,Y,t(X;14)(p11.4;p12), which was inherited from his mother. The testis biopsies indicated the arrest of spermatogenesis. There were no microdeletions of the azoospermia factor a (AZFa), AZFb and AZFc regions in the Y chromosome shown by PCR with 11 sequence-tagged site (STS) markers. According to the literature, male carriers of an X-autosome translocation are invariably sterile, regardless of the position of the break-point in the X chromosome. To our knowledge, this is the first case report of azoospermia with t(X;14)(p11.4;p12) in Korea.

An infertile 45,X male carrying an unbalanced(Y,13) translocation:A clinical cytogenetic and molecular study / 医学研究生学报

Objective: To report a case of azoospermia with a karyotype of 45,X,der(Y)t(Y;13)(q11.2;q12),-13,accompanied with slight bilateral gynecomastia and multiple nodules.Methods: The karyotype was identified by karyotyping and FISH,and the breakpoints of the Y chromosome and the copy number of the BRCA2 gene in 13q12 determined by PCR-STS and DNA polymorphic analysis.The testis and nodule tissues of the patient were obtained for biopsy.Results: FISH confirmed SRY and centromere of the Y chromosome on the questionable 13 chromosome and the karyotype to be 45,X,der(Y)t(Y;13)(q11.1;q12),-13.ish der(Y)(SRY+,DYZ3+,wcp13+).PCR-STS showed the deletion of regions AZFa,b and C,with a breakpoint located inYq11.1 below sY82.No deletion of the BRCA2 gene was observed.The patient was diagnosed with Sertoli cell-only syndrome by testicular biopsy and with angiolipomata by pathological examination of the nodule tissue.Conclusion: The patient's phenotype of complete masculinization could be attributed to presence of the SRY gene,and his azoospermia with small testis to the absence of a fragment from Yq11.1 to Yqter.However,the molecular mechanism of angiolipoma remains unknown.

A Case of Azoospermia Associated with Y - Autosome Translocation / 대한산부인과학회잡지

Aneuploidy results from nondisjunction in either the meiotic division of the parents or the early cleavage divisions of the affected individuals. The sex chromosomes show a wide range of viable aneuploidy than do the autosomes. The incidence of 47,XXY and 47,XYY children increases with maternal age, as does that of autosomal trisomies, whereas the incidence of 45,X children does not increase with maternal age. In the group of sex chromosome aueuploidies, the 47,XXY and 47,XYY conditions occur with nearly equal hequency at birth. Translocations between X or Y chromosomes and an autosome or between an X chromosome and the Y chromosome cause sterility in human males. It has been assumed that a translocation involving either(or both) of the sex chromosomes would interfere with inactivation of the XY bivalent and thaeby disturb spermatogenesis. We bave experienced a case of Y-autosome translocation in azoospermic patient. So we report this case with a brief review of literatures.

Application of autosomal STR genetic markers in siblings identification / 中国法医学杂志

Objective To discuss the probability of siblings identification by autosomal short tandem repeat (STR). Methods 150 pairs of full siblings and 150 pairs of unrelated individuals were genotyped by the 15 STR loci of Power Plex?6 system. Paternity index of full siblings (Pips) and paternity probability of full siblings (WFS) were calculated with the method of ITO. WFS and allelic matching of the two groups were compared, and three sorts of allelic matching in each pair were tested by chi-square test. Results Wps of 100 pairs of siblings (66.67%) were more than 0.9995; WFS of unrelated individuals were less than 0.8, and that of 100 pairs (66.67%) were less than 0.27. The locus number of the entire-same ranged from 1 to 10, averaged 5.49 in siblings, while in unrelated individuals ranged from 0 to 5 and averaged 1.33; that of the entire-different ranged from 0 to 6, averaged 1.66 in siblings but ranged from 2 to 11 and averaged 6.57 in unrelated individuals; that of the half-same ranged from 3 to 13, averaged 7.85 in siblings, and ranged from 1 to 13, averaged 7.11 in unrelated individuals. By chi-square test, there was significant difference (P0.05) in the half-same between the two groups. Conclusion It is effective to identify siblings by Power-Plex?6 system. Testing of 15 STR loci of PowerPlex?6 system, it suggested that the pair were unrelated individuals when the locus number of the entirely-different is not less than 6 or that of the entirely-same is zero, and that the pair were siblings when the locus number of entirely-different is not more than 1 or that of the entirely-same is not less than 6.