Allele frequencies of the six miniSTR loci in a population from Japan

Allele frequencies and forensic parameters for the six miniSTR loci D1S1677, D2S441, D4S2364, D10S1248, D14S1434, and D22S1045 were investigated in a sample of 142 unrelated healthy Japanese individuals. The polymerase chain reaction (PCR) products contained within the six loci were less than 119 bp in size. The frequency distributions in the six short tandem repeat (STR) loci showed no deviations from Hardy–Weinberg equilibrium expectations. The accumulated powers of discrimination and power of exclusion for the six loci were 0.999998 and 0.98, respectively. It was thus considered that due to the small PCR products and the moderate degree of polymorphism, analysis with use of the six miniSTR loci was highly beneficial for the forensic analysis of degraded DNA.     

Population genetic data for ten miniSTR loci in the Sri Lankan population

Allele frequencies and forensically important parameters of ten autosomal miniSTR loci, D1S1677, D2S1776, D10S1248, D11S4463, D12SATA, D14S1434, D17S974, D18S853, D20S482, and D22S1045, were obtained for 278 unrelated adults from the Sri Lankan population. The combined power of discrimination and probability of exclusion was found to be 0.999999999621539 and 0.9979620, respectively. No significant deviations from Hardy–Weinberg equilibrium were observed except for D20S482 which conformed to HW expectations only after the application of a Bonferroni correction. The study suggests the potential use of these miniSTRs as a supplement or as a stand-alone STR marker system for the analysis of highly degraded evidence in Sri Lanka.

     

Forensic and population genetic analyses of eighteen non-CODIS miniSTR loci in the Korean population

We analyzed the variation of eighteen miniSTR loci in 411 randomly chosen individuals from Korea to increase the probability that a degraded sample can be typed, as well as to provide an expanded and reliable population database. Six multiplex PCR systems were developed (multiplex I: D1S1677, D2S441 and D4S2364; multiplex II: D10S1248, D14S1434 and D22S1045; multiplex III: D12S391, D16S3253 and D20S161; multiplex IV: D3S4529, D8S1115 and D18S853; multiplex V: D6S1017, D11S4463 and D17S1301; multiplex VI: D5S2500, D9S1122 and D21S1437). Allele frequencies and forensic parameters were calculated to evaluate the suitability and robustness of these non-CODIS miniSTR systems. No significant deviation from Hardy–Weinberg equilibrium expectations were observed, except for D4S2364, D5S2500 and D20S161 loci. A multidimensional scaling plot based on allele frequencies of the six miniSTR loci (D1S1677, D2S441, D4S2364, D10S1248, D14S1434 and D22S1045) showed that Koreans appeared to have most genetic affinity with Chinese and Japanese than to other Eurasian populations compared here. The combined probability of match calculated from the 18 miniSTR loci was 2.902 × 10^?17, indicating a high degree of polymorphism. Thus, the 18 miniSTR loci can be suitable for recovering useful information for analyzing degraded forensic casework samples and for adding supplementary genetic information for a variety of analyses involving closely related individuals where there is a need for additional genetic information.     

Forensic genetic analysis of nine miniSTR loci in the Korean population

Nine miniSTR loci were analyzed in 191 unrelated individuals from Korea using three multiplex PCR systems (multiplex I: D1S1677, D2S441 and D4S2364; multiplex II: D10S1248, D14S1434 and D22S1045; multiplex III: D12S391, D16S3253 and D20S161). Due to the short PCR amplicons (<145 bp), miniSTR systems can effectively be used in forensic analysis with highly degraded DNAs. Allele frequencies and forensic parameters were calculated to evaluate their usefulness in forensic casework. The Exact Test demonstrated that all loci surveyed here were found to be no deviation from Hardy–Weinberg equilibrium, except two miniSTR markers (D4S2364 and D16S3253). When we compared the distribution of genetic variation of six miniSTR markers (D1S1677, D2S441, D4S2364, D10S1248, D14S1434 and D22S1045), the Exact Test revealed significant differences (P < 0.05) between the Korean sample studied here and almost all of other samples of East Asian and European populations. The combined probability of match calculated from nine miniSTR loci was 1.28 × 10⁻⁸, which is high degree of polymorphism. Thus, the miniSTR system, combined with other valuable miniSTR markers, may be suitable for recovering useful information in analyzing degraded DNA samples.     

Developmental validation of Mini-DogFiler for degraded canine DNA

Dogs (Canis lupus familiaris) are kept as pets in 39% of American households and are, therefore, a significant source of potentially probative biological evidence. As with any biological evidence, degradation can occur as a consequence of environmental exposure causing fracturing of the DNA and a resulting loss of intact template. Degraded human DNA analysis has benefited from the application of primer sets that amplify shorter nuclear sequences for core STR loci (miniSTRs), resulting in improved DNA profiles. This same approach was applied to our core canine STR loci. The 16-locus “DogFiler” panel was redesigned into three panels of miniSTRs for analysis of degraded canine DNA, with all primer pairs producing amplicons below 205 base pairs in length. These new miniSTR marker panels – known as Mini-DogFiler – were validated according to SWGDAM guidelines, and concordance with the original 16-locus multiplex was demonstrated through genotyping 1244 samples. The combination of these miniSTRs and a half-volume reaction increased the amplification success of degraded and low copy number canine biological samples resulting in a near three-fold increase in reportable alleles. This assemblage of miniSTRs along with the DogFiler panel and associated allelic ladder are the first non-human DNA profiling system to parallel the human forensic paradigm.     

Population genetics of six miniSTR loci (D1S1677, D2S441, D4S2364, D10S1248, D14S1434, D22S1045) in a Polish population

Allele frequency data and forensic efficiency parameters for six miniSTR loci: D1S1677, D2S441, D4S2364 (NC01), D10S1248, D14S1434, D22S1045 (NC02) were estimated from a sample of 116 unrelated individuals from Poland. No significant deviations from Hardy–Weinberg equilibrium expectations were detected. The combined power of discrimination for the six studied loci was 0.999995383.     

Genetic composition of six miniSTR in a Brazilian Mulatto sample population

The present study characterizes the genetic variability of Mulatto population based on the polymorphism of six miniSTR autosomal loci, known as Non Codis 01 and 02 (NC01 and NC02) and evaluate their applicability in forensic genetics. A sample of 102 unrelated Brazilian mulattoes were genotyped for miniSTR loci D1S1677, D2S441, D4S2364 (miniplex NC02) and 45 individuals for D10S1248, D14S1434, D22S1045 (miniplex NC01). No significant deviations from Hardy-Weinberg equilibrium expectations were detected. The combined power of discrimination (PD) and mean power of exclusion (PE) were 0.999996 and 0.98991, respectively. The results also support the effectiveness of the NC01and NC02 miniplexes for human identification.     

Evaluation of the Early Access STR Kit v1 on the Ion Torrent PGM™ platform

The Early Access STR Kit v1 is designed to detect 25-plex loci with next generation sequencing (NGS) technology on the Ion Torrent PGM™ platform, including 16 of 20 expanded Combined DNA Index System (CODIS) core loci (CSF1PO, D1S1656, D2S1338, D2S441, D3S1358, D5S818, D7S820, D8S1179, D10S1248, D13S317, D16S539, D19S433, D21S11, TH01, TPOX and vWA), 8 non-CODIS core loci (D1S1677, D2S1776, D4S2408, D5S2500.AC008791, D6S1043, D6S474, D9S2157 and D14S1434) and Amelogenin. In this study, we compared the Early Access STR Kit v1 with the Ion Torrent™ HID STR 10-plex to find out its improvements and explored an appropriate analytical threshold to enhance the performance. In addition, seven experiments were conducted to evaluate the Early Access STR Kit v1 such as studies of repeatability, concordance, sensitivity, mixtures, degraded samples, case-type samples and pedigrees. Other than a little discordance (0.95%) with CE-STR results observed at D21S11, NGS-STR results correctly reflected the sample being tested. Repeatable results were obtained from both initial PCRs and emPCRs aside from a few variations of allele coverage. Full profiles could be obtained from 100 pg input DNA and >48.84% profiles from 10 pg input DNA. Mixtures were easily detected at 9:1 and 1:9 ratios. This system could be adapted to case-type samples and degraded samples. As a whole, the Early Access STR Kit v1 is a robust, reliable and reproducible assay for NGS-STR typing and a potential tool for human identification.     

Fourteen non-CODIS autosomal short tandem repeat loci multiplex data from Taiwanese

Interest in the development of polymorphic short tandem repeat (STR) markers unlinked to the CODIS loci is growing among forensic practitioners. We developed a multiplex system in which14 autosomal STR (D3S1744, D4S2366, D8S1110, D12S1090, D13S765, D14S608, Penta E, D17S1294, D18S536, D18S1270, D20S470, D21S1437, Penta D, and D22S683) could be amplified in one single polymerase chain reaction. DNA samples from 572 unrelated Taiwanese Han subjects were analyzed using this 14 STR multiplex system. Thirty parent–child pairs of parentage testing cases with a combined paternity index (CPI) below 1,000 and 32 parent–child pairs with single-step mutations found in AmpFℓSTR Identifiler loci were also recruited for validation of the newly developed system. DNA sequencing was performed for novel STRs and novel alleles found in these subjects. The distributions of allelic frequencies for these autosomal STRs and sequence data, allele nomenclature for the STRs, and forensic parameters are presented. The discrimination power in our multiplex loci ranged from 0.6858 (D18S536) to 0.9168 (Penta E), with a combined discrimination power of 0.999999999. It provides additional power to distinguish the possible single-step mutations in parent–child pairs and improves the ability to prove parentage by increasing the CPI. The combined power of exclusion of these 14 loci in Taiwanese Han in this study was 0.9999995913. In conclusion, this 14-autosomal STRs multiplex system provides highly informative STR data and appears useful in forensic casework and parentage testing.     

Genetic polymorphism studies on 22 autosomal STR loci of the PowerPlex Fusion System in Bangladeshi population

Genetic polymorphism of 22 autosomal STR loci included in PowerPlex® Fusion System (D3S1358, D1S1656, D2S441, D10S1248, D13S317, Penta E, D16S539, D18S51, D2S1338, CSF1PO, Penta D, TH01, vWA, D21S11, D7S820, D5S818, TPOX, D8S1179, D12S391, D19S433, FGA and D22S1045) was studied in 188 unrelated Bangladeshi Bengali individuals. Allele frequencies and forensic efficiency parameters such as, the power of discrimination (PD), observed and expected heterozygosity (Ho & He), polymorphism information content (PIC), probability of match (PM), power of exclusion (PE) and typical paternity index was calculated for the loci. The combined PM and PE for all 22 STR loci were calculated to be 5.29 × 10⁻²⁷ and 0.99999999945 respectively. The dataset indicated the usefulness of these loci in personal identification, parentage testing and complex kinship analysis in Bangladeshi population. A neighbor-joining tree was constructed based on pair-wise Nei’s genetic distance by comparing allele frequency data for the 22 loci with six other populations. The analysis showed that Bangladeshi population lies closer to a clade consisting Japan, the Philippines and East Timot populations.     

Population data on 10 non-CODIS STR loci in Japanese population using a newly developed multiplex PCR system

This paper describes a newly devised autosomal short tandem repeat (STR) multiplex polymerase chain reaction (PCR) systems for 10 loci (D1S1656, D2S1353, D8S1132, D12S1090, D14S608, D18S535, D19S253, D20S480, D21S226, and D22S689) unlinked to the core STR loci (non-CODIS loci). Of 252 samples taken from the Japanese population, PCR products ranged in length from 107 bp to 319 bp. No significant deviations from Hardy–Weinberg equilibrium were observed at any of the 10 loci. The accumulated power of discrimination and power of exclusion for the 10 loci were 0.999999999998 and 0.99991, respectively. We conclude that the present multiplex system for the 10 non-CODIS loci represents a powerful tool for forensic applications.     

Genetic variation of 15 autosomal STR loci in a population sample from Poland

Fifteen autosomal STR loci included in AmpF?STR® NGM? kit were analyzed in 154 unrelated individuals from Poland. This multiplex kit enables simultaneous amplification of 10 standard STR loci included in AmpF?STR® SGM Plus® kit (D3S1358, vWA, D16S539, D2S1338, D8S1179, D19S433, TH01, FGA, D21S11 and D18S51) and five new mini- and midi-STR loci (D10S1248, D22S1045, D2S441, D1S1656 and D12S391). Population study was conducted to evaluate usefulness of the loci (especially the five new microsatellite systems) in forensic genetic identification examinations. All 15 markers were found to be in Hardy–Weinberg equilibrium. The combined probability of match for the 15 studied STR loci was 3.998 × 10^?19. The same parameter calculated for five new microsatellite loci equaled 8.83 × 10^?7. Discrimination power was particularly high in case of D1S1656 (0.975) and D12S391 (0.972) STR loci.     

Forensic value of nine STR loci in Northern Thai

Nine STR loci (D3S1358, D5S818, D7S820, D8S1179, D13S317, TH01, VWA, TPOX, LPL) were studied in a large Northern Thai population sample. All loci meet Hardy-Weinberg expectations. The combined power of discrimination and exclusion is 0.9999999979 and 0.99798 respectively. Mutation rates for STR loci did not exceed 1-4 per 1000 parent/child pairs as derived from disputed paternity cases. Similar mutation rates were also reported from other populations. No mutations were found for D5S818, D7S820, TH01, and TPOX.     

Allele frequencies of the new European Standard Set (ESS) loci in a population of Apulia (Southern Italy)

Allele frequencies of five miniSTRs loci (D1S1656, D2S441, D12S391, D10S1248 and D22S1045) included in the new European Standard Set (ESS) were calculated from a sample of 150 unrelated individuals from Apulia, a Region of Southern Italy. Two different PCR Amplification Kits were used, in order to evaluate the concordance of the genotypes. The results obtained with the two kits showed no differences in all genotype profiles. No deviation from Hardy–Weinberg expectations was detected at either locus. Moreover genetic analysis using Fst estimation showed no evidence for differentiation at the five new loci between Apulia and Italian populations. The high levels of polymorphisms of the analyzed markers in the Apulian population allow to confirm that these markers are useful tools in paternity and forensic analysis from degraded DNA samples.     

STRs vs. SNPs: thoughts on the future of forensic DNA testing

Largely due to technological progress coming from the Human Genome and International HapMap Projects, the issue has been raised in recent years within the forensic DNA typing community of the potential for single nucleotide polymorphism (SNP) markers as possible replacements of the currently used short tandem repeat (STR) loci. Our human identity testing project team at the U.S. National Institute of Standards and Technology (NIST) has explored numerous SNP and STR loci and assays as well as developing miniSTRs for degraded DNA samples. Based on their power of discrimination, use in deciphering mixture components, and ability to be combined in multiplex assays in order to recover information from low amounts of biological material, we believe that STRs rather than SNPs will fulfill the dominant role in human identity testing for the foreseeable future. However, SNPs may play a useful role in specialized applications such as mitochondrial DNA (mtDNA) testing, Y-SNPs as lineage markers, ancestry informative markers (AIMs), the prediction of phenotypic traits, and other potential niche forensic casework applications. Official disclaimer: Contribution of the U.S. National Institute of Standards and Technology. Not subject to copyright. Points of view in this document are those of the authors and do not necessarily represent the official position or policies of the U.S. Department of Justice. Certain commercial equipment, instruments and materials are identified in order to specify experimental procedures as completely as possible. In no case does such identification imply a recommendation or endorsement by the National Institute of Standards and Technology nor does it imply that any of the materials, instruments, or equipment identified are necessarily the best available for the purpose. This work was funded in part by the National Institute of Justice through interagency agreement 2003-IJ-R-029 with the NIST Office of Law Enforcement Standards.     

Genetic diversity of nine STRs in two northwest Iberian populations: Galicia and northern Portugal

The genotyping of two population samples from Galicia and northern Portugal was performed for nine STR loci using a single multiplex reaction with the AmpFlSTR Profiler Plus PCR amplification kit which co-amplifies the systems D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820 and the X-Y homologous gene amelogenin. Allele frequencies for these nine tetranucleotide repeat markers were calculated and no significant differences were observed when comparing these two populations. Conformity with Hardy-Weinberg equilibrium proportions was good for all systems in both samples. The combined power of exclusion was 99.981% and 99.980% in Galicia and northern Portugal, respectively and the combined power of discrimination was greater than 99.999%. Segregation analysis of all loci detected two incompatibilities, one in D3S1358 (out of 112 meioses) and another in D7S820 (out of 104 meioses). Both could be explained by single-step mutations. In general co-amplification was good except for some relatively degraded samples in which poor amplification was observed for the largest STRs. Nevertheless the system is technically robust even when small amounts of template DNA are used and in addition is highly informative and time-saving. However, caution should be taken in the interpretation of profiles in degraded samples and the apparently high mutation rate of D3S1358 and D7S820 should also be kept in mind. Received: 6 April 1999 / Accepted: 16 July 1999     

Forensic evaluation of 11 non-standard STR loci in Bangladeshi population

Allele frequencies and forensic efficiency parameters of 11 non-standard autosomal STR loci, D21S1437, D22S683, D8S1110, D10S2325, D12S1090, D17S1294, D3S1744, D14S608, D20S470, D18S536 and D13S765 were evaluated in a sample of 102 unrelated Bangladeshi individuals. No significant deviation from Hardy–Weinberg equilibrium was observed in any of the loci studied. Statistical parameters of forensic importance, the power of discrimination (PD), observed and expected heterozygosity (H), polymorphism information content (PIC), matching probability (MP), power of exclusion (PE) and typical paternity index (TPI) were calculated for the loci. The most informative locus among the 11 STR loci was D10S2325 (PD = 0.958), while the least informative was D17S129 (PD = 0.876). The combined PD (1-PM) and MP was calculated to be 0.9999999999997 and 2.23 × 10^?23, respectively. These parameters indicated the usefulness of the loci in forensic personal identification and parentage testing among Bangladeshi population.     

Polymorphism analysis of 15 STR loci in a large sample of the Han population in southern China

We have conducted genotyping experiments on 15 STR loci in over 5000 unrelated individuals of the Han population in Southern China. The loci are D31358, TH01, D21S11, D18S51, Penta E, D5S818, D13S317, D7S820, D16S539, CSF1PO, Penta D, vWA, D8S1179, TPOX and FGA. Our statistic analysis indicates that the 15 STR loci conform to the Hardy–Weinberg's equilibrium (p > 0.05). We also report here the heterozygosity, matching probability, power of discrimination, probability of exclusion, polymorphism information content and typical paternity index for each locus. The results indicate that these loci are highly polymorphic in the Han population in Southern China.     

Investigation of single nucleotide polymorphism loci susceptible to degradation by ultraviolet light

DNA in biological fluids is often degraded by environmental factors. Given that single nucleotide polymorphism (SNP) analyses require shorter amplicons than short tandem repeat (STR) analyses do, their use in human identification using degraded samples has recently attracted attention. Although various SNP loci are used to analyze degraded samples, it is unclear which ones are more appropriate. To characterize and identify SNP loci that are susceptible or resistant to degradation, we artificially degraded DNA, obtained from buccal swabs from 11 volunteers, by exposure to ultraviolet (UV) light for different durations (254 nm for 5, 15, 30, 60, or 120 min) and analyzed the resulting SNP loci. DNA degradation was assessed using gel electrophoresis, STR, and SNP profiling. DNA fragmentation occurred within 5 min of UV irradiation, and successful STR and SNP profiling decreased with increasing duration. However, 73% of SNP loci were still detected correctly in DNA samples irradiated for 120 min, a dose that rendered STR loci undetectable. The unsuccessful SNP typing and the base call failure of nucleotides neighboring the SNPs were traced to rs1031825, and we found that this SNP was susceptible to UV light. When comparing the detection efficiencies of STR and SNP loci, SNP typing was more successful than STR typing, making it effective when using degraded DNA. However, it is important to use rs1031825 with caution when interpreting SNP analyses of degraded DNA.     

Assessment of application value of 19 autosomal short tandem repeat loci of GoldenEyeTM 20A kit in forensic paternity testing

This study was carried out to assess the application value of 19 autosomal short tandem repeat (STR) loci of GoldenEye^TM 20A kit, in which 13 combined DNA index system core STR loci and PentaE, PentaD, D2S1338, D19S433, D12S391, and D6S1043 of six STR loci could be used in forensic paternity testing in Chinese population. We amplified the genomic DNA from blood samples on FTA paper of 289 paternity testing cases by using the GoldenEye^TM 20A kit. The amplified products were detected by capillary electrophoresis, and then the genotypes of 20 genetic markers including 19 STR loci as well as Amelogenin for sex determination were analyzed by GeneMapper v3.2 and GeneMarker HID Software. The results of genotypes were compared to the three commonly used commercial kits including AmpF?STR Identifiler^TM, PowerPlex^TM16, and AmpF?STR Sinofiler^TM kits. Compared to the three other common commercial kits, the GoldenEye^TM 20A kit had higher value of combined paternity index in certainty of paternity or non-exclusion paternity cases, and more numbers of STR loci were excluded in exclusionary paternity cases. Our data in this study showed that the GoldenEye^TM 20A kit has a higher application value in forensic paternity testing and will be of help for kinship analysis.