22243051
Potential forensic application of DNA methylation profiling to body fluid identification
DNA analysis of various body fluid stains at crime scenes facilitates the identification of individuals but does not currently determine the type and origin of the biological material. Recent advances in whole genome epigenetic analysis indicate that chromosome pieces called tDMRs (tissue-specific differentially methylated regions) show different DNA methylation profiles according to the type of cell or tissue. We examined the potential of tissue-specific differential DNA methylation for body fluid identification. Five tDMRs for the genes DACT1, USP49, HOXA4, PFN3, and PRMT2 were selected, and DNA methylation profiles for these tDMRs were produced by bisulfite sequencing using pooled DNA from blood, saliva, semen, menstrual blood, and vaginal fluid. The tDMRs for DACT1 and USP49 showed semen-specific hypomethylation, and the tDMRs for HOXA4, PFN3, and PRMT2 displayed varying degrees of methylation according to the type of body fluid. Preliminary tests using methylation-specific PCR for the DACT1 and USP49 tDMRs showed that these two markers could be used successfully to identify semen samples including sperm cells. Body fluid-specific differential DNA methylation may be a promising indicator for body fluid identification. Because DNA methylation profiling uses the same biological source of DNA for individual identification profiling, the determination of more body fluid-specific tDMRs and the development of convenient tDMR analysis methods will facilitate the broad implementation of body fluid identification in forensic casework.
21885090
Quantitative and qualitative profiling of mitochondrial DNA length heteroplasmy.
Quantitative and qualitative analysis of mitochondrial DNA length heteroplasmy for the first hypervariable segment (HV1) and second hypervariable segment (HV2) regions were performed using size-based separation of fluorescently-labeled polymerase chain reaction (PCR) products by capillary electrophoresis. In this report, the relative proportions of length heteroplasmies in individuals were determined, and each length variant in the heteroplasmic mtDNA mixture was identified. The study demonstrated that 36% and 69% of Koreans show length heteroplasmy in the HV1 and HV2 regions, respectively. Electropherograms revealed that length heteroplasmy in the HV1 region resulted in over 5 length variants in an individual. The peak patterns of length heteroplasmy in the HV1 region were classified into five major types. In the HV2 region, length heteroplasmy resulted in 3-6 length variants in an individual, and showed seven variant peak patterns. The increased knowledge concerning mtDNA length heteroplasmy is believed to not only offer a useful means of determining genetic identity due to increased mitochondrial DNA haplotype diversity by allowing mtDNAs to be classified into several peak patterns, but also represent a promising tool for the diagnosis of several common diseases which are etiologically or prognostically associated with mtDNA polymorphisms.
18237995
mtDNAmanager: a Web-based tool for the management and quality analysis of mitochondrial DNA control-region sequences
BackgroundFor the past few years, scientific controversy has surrounded the large number of errors in forensic and literature mitochondrial DNA (mtDNA) data. However, recent research has shown that using mtDNA phylogeny and referring to known mtDNA haplotypes can be useful for checking the quality of sequence data.ResultsWe developed a Web-based bioinformatics resource "mtDNAmanager" that offers a convenient interface supporting the management and quality analysis of mtDNA sequence data. The mtDNAmanager performs computations on mtDNA control-region sequences to estimate the most-probable mtDNA haplogroups and retrieves similar sequences from a selected database. By the phased designation of the most-probable haplogroups (both expected and estimated haplogroups), mtDNAmanager enables users to systematically detect errors whilst allowing for confirmation of the presence of clear key diagnostic mutations and accompanying mutations. The query tools of mtDNAmanager also facilitate database screening with two options of "match" and "include the queried nucleotide polymorphism". In addition, mtDNAmanager provides Web interfaces for users to manage and analyse their own data in batch mode.ConclusionThe mtDNAmanager will provide systematic routines for mtDNA sequence data management and analysis via easily accessible Web interfaces, and thus should be very useful for population, medical and forensic studies that employ mtDNA analysis. mtDNAmanager can be accessed at http://mtmanager.yonsei.ac.kr.
42434218
Differential distribution of human mitochondrial DNA in somatic tissues and hairs.
To investigate mitochondrial DNA (mtDNA) distribution within tissues during life, we observed length heteroplasmy in a polycytosine tract of the mitochondrial HV2 region by size-based separation of PCR products, using a mutagenic primer which was designed to avoid stutter production. Blood, brain, heart, liver, skeletal muscle and hair shaft samples were collected during autopsies of 25 individuals. Here, we demonstrate differences in the level of mtDNA length heteroplasmy both within and between individuals and tissues. We also show that mtDNA is distributed randomly in varying proportions in various somatic tissues during growth, resulting in an imbalance in the composition of mtDNA pools among tissues. This mtDNA distribution appears not to be strictly random, and can be explained by the random somatic segregation of nucleoids. On the other hand, significant qualitative/quantitative mtDNA peak pattern variations in hair shafts are thought to be a result of the different developmental origins of hairs. Each hair shaft may have a restricted or clonal set of mtDNA molecules derived from a discrete group of stem cells.
22611234
Genetic characteristics and population study of 4 X-chromosomal STRs in Koreans: evidence for a null allele at DXS9898
The four X-chromosomal short tandem repeats (STRs), DXS9898, DXS6809, DXS7424 and DXS10011 were analyzed by single multiplex PCR in 150 male and 150 female Koreans. The loss of an allele at DXS9898 was observed in 13 out of 450 chromosomes (2.9%) and the PCR analysis showed that the X-chromosome with a null allele at DXS9898 has more than 1 kb deletion at the DXS9898 locus. Statistical analyses for these four X-STRs showed that they are highly informative for forensic application in Koreans. No linkage disequilibrium was observed among these four STRs and the previously reported five polymorphic STRs, HumARA, DXS101, GATA172D05, HPRTB and DXS8377 in Koreans. The test of homogeneity between allele frequencies revealed that there are some discrepancies in allele distributions between Koreans and Germans.
206716414
A one step multiplex PCR assay for rapid screening of East Asian mtDNA haplogroups on forensic samples.
The mitochondrial DNA (mtDNA) haplogroup typing has become an essential tool to study human evolutionary history and to infer the matrilineal bio-geographic ancestry. In forensic field, the screening of mtDNA haplogroups by genotyping of mtDNA single nucleotide polymorphisms (SNPs) can help guarantee the quality of mtDNA sequence data as well as can reduce the need to sequence samples that do not match. Here, a multiplex mutagenically separated (MS) polymerase chain reaction (PCR) system was developed for simultaneous rapid detection of 14 coding region SNPs and one deletion motif representing common mtDNA haplogroups of East Asia. The multiplex MS PCR system we developed has the advantage of being a one step procedure that requires only a single PCR amplification with allele-specific primers and allowing straightforward designation of haplogroups along the branches of the phylogenetic tree. Therefore, it would be a simple, rapid, and reliable detection method useful for large-scale screening of mtDNA variations to determine East Asian mtDNA haplogroups.
9720261
Xanthogranulomatous prostatitis: a rare entity resembling prostate adenocarcinoma with magnetic resonance image picture.
Granulomatous prostatitis, characterized by chronic granulomatous inflammation in the prostate, is rare. Xanthogranulomatous prostatitis is an even rarer granulomatous inflammation. We present a 74-year-old man who presented with lower urinary tract symptoms and elevated prostate specific antigen. A transrectal ultrasonography-guided prostate biopsy was performed, and pathological results showed foamy macrophage and inflammatory cell infiltrates, which were a distinctive feature of xanthogranulomatous prostatitis. We also present the characteristics of magnetic resonance imaging in xanthogranulomatous prostatitis which has never been previously described.
17577030
Human originated bacteria, Lactobacillus rhamnosus PL60, produce conjugated linoleic acid and show anti-obesity effects in diet-induced obese mice.
Many previous studies have reported that conjugated linoleic acid could be produced by starter culture bacteria, but the effects of the bacteria were not investigated. Moreover, there was no evidence of the conjugated linoleic acid-producing bacteria having potential health or nutritional effects related to conjugated linoleic acid, including reducing body fat. Here, we investigated the anti-obesity effect of Lactobacillus rhamnosus PL60, a human originated bacterium that produces t10, c12-conjugated linoleic acid, on diet-induced obese mice. After 8 weeks of feeding, L. rhamnosus PL60 reduced body weight without reducing energy intake, and caused a significant, specific reduction of white adipose tissue (epididymal and perirenal). Although the size of epididymal adipocytes was not reduced by L. rhamnosus PL60, apoptotic signals and UCP-2 mRNA levels increased in adipose tissue. Liver steatosis, a well known side effect of CLA, was not observed by L. rhamnosus PL60 treatment; on the contrary it seemed to be normalized. Results showed that the amount of conjugated linoleic acid produced by Lactobacillus rhamnosus PL60 was enough to produce an anti-obesity effect.
43136894
Acute oliguric renal failure associated with angiotensin II receptor antagonists.
2859155
Bioassay-Guided Evolution of Glycosylated Macrolide Antibiotics in Escherichia coli
Macrolide antibiotics such as erythromycin are clinically important polyketide natural products. We have engineered a recombinant strain of Escherichia coli that produces small but measurable quantities of the bioactive macrolide 6-deoxyerythromycin D. Bioassay-guided evolution of this strain led to the identification of an antibiotic-overproducing mutation in the mycarose biosynthesis and transfer pathway that was detectable via a colony-based screening assay. This high-throughput assay was then used to evolve second-generation mutants capable of enhanced precursor-directed biosynthesis of macrolide antibiotics. The availability of a screen for macrolide biosynthesis in E. coli offers a fundamentally new approach in dissecting modular megasynthase mechanisms as well as engineering antibiotics with novel pharmacological properties.
11860293
Changing patterns in the association between regional socio-economic context and dental caries experience according to gender and age: A multilevel study in Korean adults
BackgroundLittle is known about the effects of socio-environmental factors on dental caries in different demographic situations in Asian populations. We investigated whether the nature of the association between regional socio-economic context and dental caries experience differed according to gender and age groups in Korean adults.MethodsWe obtained a linked data set containing individual information from the 2000 Korean National Oral Health Survey and regional information from the “Major statistical indices of Si-Gun-Gu” (city-county-ward), published by the Korean Statistical Office. We stratified participants into women and men and into four 10-year-interval age groups (19–34, 35–44, 45–54, and 55–64 years) and analysed the linked data using a multilevel analysis. In total, 5,259 individuals were included in the final study population.ResultsRegional socio-economic context was significantly associated with dental caries experience in men, but not in women. The patterns of the association between regional contextual variables and dental caries experience differed among age groups. People 35–44 years of age living in areas less dependent on the manufacturing industry and those 45–54 years of age living in areas where local government was relatively poor were more prone to have caries experience.ConclusionsThe results of this study indicated that socio-economic factors affecting residents’ dental health status may operate through different mechanisms or degrees according to geographic location, suggesting that some gender- and age-defined subgroups may be likely to benefit from different types of intervention, including the development of specific health policies.