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In case of paternity or maternity investigations with short tandem repeat (STR) analysis, deficient cases, missing person, or mutations are encountered and common STRs cannot provide sufficient forensic parameters. Thus, it is recommended that additional STRs are needed to complement conventional analysis for more reliable forensic information. We analyzed variation of 23 STRs contained in the new PowerPlex® ESX 17 kit (Promega) and two conventional kits of the AmpFlSTR Identifiler® (Applied Biosystems) and PowerPlex® 16 systems (Promega) in 452 randomly chosen individuals from Korea to provide an expanded and reliable Korean database. Allele frequencies and forensic parameters were used to evaluate suitability and robustness of the new kit for forensic genetic analysis as well as in concordance studies. The combined probability of match for the 16 loci in the PowerPlex® ESX 17 system was 2.76×10−20. One genotyping discrepancy due to a null allele was observed at the D18S51 locus (the concordant rate=99.99%), showing a primer-binding site mutation in the sequence of the locus (G-to-A substitution at position 146 of Genbank accession number JX018211). Thus, the new kit is a valuable forensic tool and is suitable to extend the Korean population genetic data obtained with well-established polymerase chain reaction multiplex-kits of the AmpFlSTR Identifiler® and PowerPlex® 16 systems. [ABSTRACT FROM AUTHOR]

Abstract: Current forensic DNA typing is conducted in approximately 8–9h. Whole steps included DNA extraction step, Quantification, PCR amplification step, electrophoresis process through capillary separation with fluorescence detection, data analysis and DNA profile interpretation. Among them, we have tested rapid PCR method of AmpFlSTR Identifler PCR to reduce running time. We have altered several PCR conditions of ordinary AmpFlSTR Identifler PCR method and used 9947A control DNA to cut the time for the PCR reaction. In the results of this study, the critical step of the PCR reaction was the annealing step and also we reduced PCR running times by 1/3 to 2/3 (approximately 60–90min) with complete concordance of STR allele calls using standard reference material 9947A. [Copyright &y& Elsevier]

Abstract: Haplotypes and allele frequencies of 12 STR loci included in the PowerPlex® Y system (DYS391, DYS389I, DYS439, DYS389II, DYS438, DYS437, DYS19, DYS392, DYS393, DYS390, and DYS385a/b) were obtained from a sample of 569 unrelated individuals living in the central region of Korea. A total of 473 haplotypes were observed in the 569 individuals studied, of which 426 (90.06%) were unique. The overall haplotype diversity for the 12 Y-STR loci was 0.9985, and the discrimination capacity was 0.8313. In DYS439, we found a new intermediate-sized allele that added an A at base 3 upstream from the repeat region''s first GATA motif. The allele was named 11 (U3Ains) according to its sequence structure. [Copyright &y& Elsevier]

Dogs have long shared close relationships with many humans. Due to the large number of dogs in human populations, they are often involved in crimes. Occasionally, canine biological evidence such as saliva, bloodstains and hairs can be found at crime scenes. Accordingly, canine DNA can be used as forensic evidence. The use of short tandem repeat (STR) loci from biological evidence is valuable for forensic investigations. In Korea, canine STR profiling-related crimes are being successfully analyzed, leading to diverse crimes such as animal cruelty, dog-attacks, murder, robbery, and missing and abandoned dogs being solved. However, the probability of random DNA profile matches cannot be analyzed because of a lack of canine STR data. Therefore, in this study, 10 STR loci were analyzed in 600 dogs in Korea (344 dogs belonging to 30 different purebreds and 256 crossbred dogs) to estimate canine forensic genetic parameters. Among purebred dogs, a separate statistical analysis was conducted for five major subgroups, 97 Maltese, 47 Poodles, 31 Shih Tzus, 32 Yorkshire Terriers, and 25 Pomeranians. Allele frequencies, expected (Hexp) and observed heterozygosity (Hobs), fixation index (F), probability of identity (P(ID)), probability of sibling identity (P(ID)sib) and probability of exclusion (PE) were then calculated. The Hexp values ranged from 0.901 (PEZ12) to 0.634 (FHC2079), while the P(ID)sib values were between 0.481 (FHC2079) and 0.304 (PEZ12) and the P(ID)sib was about 3.35 × 10(-)⁵ for the combination of all 10 loci. The results presented herein will strengthen the value of canine DNA to solving dog-related crimes., Competing Interests: There is no conflict of interest.

Background: Koreans are generally considered a Northeast Asian group, thought to be related to Altaic-language-speaking populations. However, recent findings have indicated that the peopling of Korea might have been more complex, involving dual origins from both southern and northern parts of East Asia. To understand the male lineage history of Korea, more data from informative genetic markers from Korea and its surrounding regions are necessary. In this study, 25 Y-chromosome single nucleotide polymorphism markers and 17 Y-chromosome short tandem repeat (Y-STR) loci were genotyped in 1,108 males from several populations in East Asia., Results: In general, we found East Asian populations to be characterized by male haplogroup homogeneity, showing major Y-chromosomal expansions of haplogroup O-M175 lineages. Interestingly, a high frequency (31.4%) of haplogroup O2b-SRY465 (and its sublineage) is characteristic of male Koreans, whereas the haplogroup distribution elsewhere in East Asian populations is patchy. The ages of the haplogroup O2b-SRY465 lineages (~9,900 years) and the pattern of variation within the lineages suggested an ancient origin in a nearby part of northeastern Asia, followed by an expansion in the vicinity of the Korean Peninsula. In addition, the coalescence time (~4,400 years) for the age of haplogroup O2b1-47z, and its Y-STR diversity, suggest that this lineage probably originated in Korea. Further studies with sufficiently large sample sizes to cover the vast East Asian region and using genomewide genotyping should provide further insights., Conclusions: These findings are consistent with linguistic, archaeological and historical evidence, which suggest that the direct ancestors of Koreans were proto-Koreans who inhabited the northeastern region of China and the Korean Peninsula during the Neolithic (8,000-1,000 BC) and Bronze (1,500-400 BC) Ages.

Nanocrystalline Silver-supported activated carbon (AC) was fabricated by directly loading silver nanoparticles into the porous AC matrix from a preformed nanosilver hydrosol. Silver-AC composites were also synthesized using a conventional thermal impregnation method. While XRD calculation indicated the presence of Ag crystallites in nanometer range, silver nanoparticle hydrosol-treated AC having the finest crystallite size CS (< 14.4 nm), SEM images clearly revealed that Ag crystals coalesced significantly with increasing temperature resulting in much larger particle size in thermally impregnated silver-AC composities. To clarify the antibacterial mechanism of silver nanoparticles impregnated into AC under prolonged incubation conditions the antibacterial activity was investigated against Gram-negative Escherichia coli. The kinetics of bacterial inactivation, in presence of hydroxyl radical (*OH) scavengers, and superoxide anion radical (*O2-) inducer suggest the contribution of the reactive oxygen species (ROS) to antibacterial effect. However, these ROS scavengers did not show any inhibition of bactericidal activity after approximately 1 h, suggesting that generated ROS are responsible for E. coli inactivation only during the initial 1 h of the incubation time. This study clearly indicates the plausible implication of eluted Ag+ as major lethal species responsible for the E. coli inactivation over extended process time. The antibacterial process was found to be highly promoted at higher temperature which was ascribed to the enhanced ROS formation and Ag+ elution at higher temperature. SEM images revealed considerable differences in the morphology of E. coli cells contacting with the virgin AC and that contacting with silver-supported AC. The strong antibacterial ability of formaldehyde-modified silver-supported AC further provided the indirect evidences for catalytic oxidation by ROS, and for the synergistic antibacterial effects of nanocrystalline silver and adsorbed formaldehyde. Comparison of the antibacterial activities of the silver-supported materials prepared by silver colloid deposition and by conventional thermal impregnation technique indicates that former is more efficient in controlling microorganism.