OBJECTIVES: To determine the disparity in the rate people undergo health examinations according to socioeconomic position (SEP) and the changes in this disparity with time. METHODS: Seoul citizens}health profile data from 1997 to 2005 were analyzed. The study subjects were 40 years old and over, and the total number of subjects was 6,601 in 1997, 8,994 in 2001, and 8,819 in 2005. Those aged 60 years and over were eliminated from the analysis of subjects}occupation. We used education, family income and occupation as indicators of SEP. The age-standardized health examination attendance rate for each year was calculated according to the education, family income and occupation. The odds ratios (ORs) from multiple logistic regressions were adjusted for age. RESULTS: The disparity in the rate of attendance according to the SEP decreased from 1997 to 2005 but still existed. Even though the disparities among the subgroups according to education, family income and occupation were not that high, the disparity between the group with the highest SEP and the other groups was considerable. CONCLUSIONS: Our findings suggest that unequal access to health examination services according to socioeconomic position still exists. This disparity has decreased recently but the disparity according to level of education was the greatest.
Adult ; Female ; Health Services Accessibility/*statistics & numerical data/trends ; Humans ; Korea ; Male ; Middle Aged ; Physical Examination/*statistics & numerical data/trends ; Socioeconomic Factors

Mitochondrial DNA (mtDNA) genome analysis has been a potent tool in forensic practice as well as in the understanding of human phylogeny in the maternal lineage. The traditional mtDNA analysis is focused on the control region, but the introduction of massive parallel sequencing (MPS) has made the typing of the entire mtDNA genome (mtGenome) more accessible for routine analysis. The complete mtDNA information can provide large amounts of novel genetic data for diverse populations as well as improved discrimination power for identification. The genetic diversity of the mtDNA sequence in different ethnic populations has been revealed through MPS analysis, but the Korean population not only has limited MPS data for the entire mtGenome, the existing data is mainly focused on the control region. In this study, the complete mtGenome data for 186 Koreans, obtained using Ion Torrent Personal Genome Machine (PGM) technology and retrieved from rather common mtDNA haplogroups based on the control region sequence, are described. The results showed that 24 haplogroups, determined with hypervariable regions only, branched into 47 subhaplogroups, and point heteroplasmy was more frequent in the coding regions. In addition, sequence variations in the coding regions observed in this study were compared with those presented in other reports on different populations, and there were similar features observed in the sequence variants for the predominant haplogroups among East Asian populations, such as Haplogroup D and macrohaplogroups M9, G, and D. This study is expected to be the trigger for the development of Korean specific mtGenome data followed by numerous future studies.

In addition to identifying genetic differences between target populations, it is also important to determine the impact of genetic differences with regard to the respective target populations. In recent years, there has been an increasing number of cases where this approach is needed, and thus various statistical methods must be considered. In this study, genetic data from populations of Southeast and Southwest Asia were collected, and several statistical approaches were evaluated on the Y-chromosome short tandem repeat data. In order to develop a more accurate and practical classification model, we applied gradient boosting and ensemble techniques. To infer between the Southeast and Southwest Asian populations, the overall performance of the classification models was better than that of the decision trees and regression models used in the past. In conclusion, this study suggests that additional statistical approaches, such as data mining techniques, could provide more useful interpretations for forensic analyses. These trials are expected to be the basis for further studies extending from target regions to the entire continent of Asia as well as the use of additional genes such as mitochondrial genes.
Asia ; Asian Continental Ancestry Group* ; Classification* ; Data Mining* ; Decision Trees ; Ethnic Groups* ; Genes, Mitochondrial ; Health Services Needs and Demand ; Humans ; Microsatellite Repeats ; Models, Statistical

BACKGROUND: Mitochondrial heteroplasmy, the co-existence of different mitochondrial polymorphisms within an individual, has various forensic and clinical implications. But there is still no guideline on the application of massively parallel sequencing (MPS) in heteroplasmy detection. We present here some critical issues that should be considered in heteroplasmy studies using MPS. METHODS: Among five samples with known innate heteroplasmies, two pairs of mixture were generated for artificial heteroplasmies with target minor allele frequencies (MAFs) ranging from 50% to 1%. Each sample was amplified by two-amplicon method and sequenced by Ion Torrent system. The outcomes of two different analysis tools, Torrent Suite Variant Caller (TVC) and mtDNA-Server (mDS), were compared. RESULTS: All the innate heteroplasmies were detected correctly by both analysis tools. Average MAFs of artificial heteroplasmies correlated well to the target values. The detection rates were almost 90% for high-level heteroplasmies, but decreased for low-level heteroplasmies. TVC generally showed lower detection rates than mDS, which seems to be due to their own computation algorithms which drop out some reference-dominant heteroplasmies. Meanwhile, mDS reported several unintended low-level heteroplasmies which were suggested as nuclear mitochondrial DNA sequences. The average coverage depth of each sample placed on the same chip showed considerable variation. The increase of coverage depth had no effect on the detection rates. CONCLUSION: In addition to the general accuracy of the MPS application on detecting heteroplasmy, our study indicates that the understanding of the nature of mitochondrial DNA and analysis algorithm would be crucial for appropriate interpretation of MPS results.
Computational Biology ; DNA, Mitochondrial* ; Gene Frequency ; High-Throughput Nucleotide Sequencing* ; Methods ; Sequence Analysis, DNA

Alcohol-induced flushing syndrome is one of the alcohol hypersensitivity reactions commonly found among Asian population. This study was designed to find markers that can predict this particular propensity among Korean population and to assess the applicability of this finding to build a prediction model as forensic DNA phenotyping tool to operate in practical forensic cases. Five hundred seventy unrelated Koreans were genotyped using microfluidic technology with 24 possible candidate single nucleotide polymorphism (SNP) markers. Of the 24 candidate SNPs, four markers, rs671, rs2074356, rs4646776, and rs10849915, on chromosome 12 showed statistically significant association with P-values ranging from 1.39×10⁻¹⁴ to 0.004988 among our subjects. All four markers show relatively high specificity values, ranging from 0.804651 to 0.972093, presenting their capabilities as differential SNPs that can distinguish a person with or without alcohol-induced flushing syndrome. Maneuvering these candidate SNPs as well as finding additional potential markers through future studies will help building an appropriate prediction model for Koreans that can be used as supplementary tool for individual identification.
Alcohols ; Aldehyde Dehydrogenase ; Asian Continental Ancestry Group ; Chromosomes, Human, Pair 12 ; DNA ; Flushing ; Humans ; Hypersensitivity ; Microfluidics ; Polymorphism, Single Nucleotide ; Sensitivity and Specificity

Alcohol-induced flushing syndrome is one of the alcohol hypersensitivity reactions commonly found among Asian population. This study was designed to find markers that can predict this particular propensity among Korean population and to assess the applicability of this finding to build a prediction model as forensic DNA phenotyping tool to operate in practical forensic cases. Five hundred seventy unrelated Koreans were genotyped using microfluidic technology with 24 possible candidate single nucleotide polymorphism (SNP) markers. Of the 24 candidate SNPs, four markers, rs671, rs2074356, rs4646776, and rs10849915, on chromosome 12 showed statistically significant association with P-values ranging from 1.39×10⁻¹⁴ to 0.004988 among our subjects. All four markers show relatively high specificity values, ranging from 0.804651 to 0.972093, presenting their capabilities as differential SNPs that can distinguish a person with or without alcohol-induced flushing syndrome. Maneuvering these candidate SNPs as well as finding additional potential markers through future studies will help building an appropriate prediction model for Koreans that can be used as supplementary tool for individual identification.

We have been testing familial relationships based on short tandem repeats (STRs) in families who requested it either voluntarily or by order of the court. Here, we present a summary of our 5-year experience of autosomal STR-based paternity tests. A total of 1,431 individuals from 588 cases were tested, including 878 pairs of either of the parent, and a child. Among these 588 cases, genetic information about the other parent was available only for 135 cases. Five hundred eighteen pairs were concluded to be parent-child relations, for which the median paternity index (PI) was 72,826, and the median decimal logarithm was 4.860. Autosomal mutation was observed in nine pairs (1.74%), and the pairs harbored only one mismatched locus among the 15 standard loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA). The number of mismatched loci did not increase even after additional loci were included in the study. The observed mutation rates were D13S317 (0.193%), D18S51 (0.193%), D19S433 (0.193%), FGA (0.193%), vWA (0.386%), Penta D (0.387%), and Penta E (0.193%). There were 14 pairs with two mismatched loci, which we excluded through additional tests on either autosomal or X chromosomal STRs, and mitochondrial sequencing. Although PI is useful for determining parent-child relation, it provides indirect information; it is an interpretation of the test results that is based on probability. Additional genotyping on sex chromosome and mitochondrial DNA, or participation of other family members might be beneficial for a reliable conclusion.
Child ; DNA, Mitochondrial ; Humans ; Microsatellite Repeats ; Mutation Rate ; Parent-Child Relations ; Parents ; Paternity* ; Sex Chromosomes

Fetal DNA (fDNA) detection in maternal serum is a challenge due to low copy number and the smaller size of fDNA fragments compared to DNA fragments derived from the mother. Massively parallel sequencing (MPS) is a useful technique for fetal genetic analysis that is able to detect and quantify small amounts of DNA. In this study, seven clinical samples of maternal serum potentially containing fDNA were analyzed with a commercial single nucleotide polymorphism (SNP) panel, the HID-Ion AmpliSeq™ Identity Panel, and the results were compared to those from previous studies. Reference profiles for mothers and fetuses were not available, but multiple Y chromosomal SNPs were detected in two samples, indicating that fDNA was present in the serum and thereby validating observations of autosomal SNPs. This suggests that SNP-based MPS can be valuable for fDNA detection, thereby offering an insight into fetal genetic status. This technology could also be used to detect small amounts of DNA in mixed DNA samples for forensic applications.
DNA* ; Fetus ; High-Throughput Nucleotide Sequencing ; Humans ; Mothers ; Polymorphism, Single Nucleotide

Forensic DNA phenotyping (FDP) using human externally visible characteristics (EVCs) is an emerging new technique that allows for the prediction of phenotypic traits of a person of interest using relevant sets of genetic markers. This technique predicts not only physical appearances, but also the behavioral characteristics as well as biogeographical information, serving as a powerful supplementary tool to narrow down the investigative pool in various forensic cases. Over the past few years, many countries, Europe and America being at the forefront, have conducted significant research to identify related markers for predicting pigmentation traits such as eye, hair, and skin color. Furthermore, some commercial platforms are now available for practical use in forensic cases. Korea and other Asian countries have also dedicated remarkable research to identify relevant markers to utilize FDP in forensic investigations. However, a slightly different approach is needed because Asians have limited phenotypic variations than Western populations. Thus, medically irrelevant and simple propensity traits such as smoking and alcohol consumption could be used to compensate for the limited phenotypic variations. This article is intended to inform readers about the progress and worldwide trends in EVC research, as well as the whereabouts and future prospects of FDP-related research in Korea. Although various legal and ethical disputes must be resolved beforehand, employing an FDP system can certainly be a powerful complementary tool for providing additional clues in forensic investigations.
Alcohol Drinking ; Americas ; Asian Continental Ancestry Group ; Dissent and Disputes ; DNA* ; Europe ; Genetic Markers ; Hair ; Humans ; Investigative Techniques ; Korea ; Phenotype ; Pigmentation ; Polymorphism, Single Nucleotide ; Skin Pigmentation ; Smoke ; Smoking

Xanthogranulomatous inflammation is a rare inflammatory reaction, characterized by lipid-laden macrophages, known as xanthomas, in histopathologic examination. Aggressive xanthogranulomatous inflammation often manifests as local infiltration but does not affect distant organs unless combined with rare systemic diseases. We report a case of focal xanthogranulomatous pyelonephritis (XGP) associated with severe xanthogranulomatous cholecystitis. Focal XGP was suspected in radiologic examination that showed a cystic lesion with an infiltrative margin, which were surgically resected and confirmed in pathologic examination. To our knowledge, this is the first report of focal xanthogranulomatous pyelonephritis associated with xanthogranulomatous cholecystitis. Moreover, we found peripheral hypointensity around the cystic lesion in the T2-weighted image, probably reflecting hemorrhage and fibrosis of the xanthogranulomatous inflammation.