• Korean Journal of Biological Psychiatry
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• v.9 no.1
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• pp.8-14
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• 2002

Patients with attention deficit hyperactivity disorder(ADHD) have symptoms of inattention, hyperactivity, impulsivity. Symptoms of ADHD are responsive to medications such as methylphenidate, dextroamphetamine, pemoline, and bupropion. The functional change of the dopamine transporter is related to the therapeutic effect of these drugs. This can be one reason for the dopamine transporter to be emphasized in the research field of ADHD. ADHD has a genetic tendency. Since dopamine transporter gene(DAT1) knock out mice were reported to be several times more active than normal mice in a novel situation, lights has been shed on DAT1 as a candidate gene for ADHD. Though there have been several studies which reported an association between DAT1 and ADHD, the association between DAT1 and ADHD is not conclusive. Since Vandenbergh reported the DAT1 polymorphism with variable number of tandem repeats(VNTR), and the racial differences in allelic frequencies of the DAT1, wide ethnic variation in the distribution of the DAT1 polymorphism had been confirmed. Wide ethnic variation in the distribution of the DAT1 suggested that there might be ethnic difference in the association between DAT1 and ADHD. Before applying previous findings to Koreans, verification might be needed for Korean patients with ADHD.

• Parasites, Hosts and Diseases
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• v.46 no.2
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• pp.105-108
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• 2008

Although the Korean isolate KI-1 of Toxoplasma gondii has been considered to be a virulent type I lineage because of its virulent clinical manifestations, its genotype is unclear. In the present study, genotyping of the KI-1 was performed by multilocus PCR-RFLP and microsatellite sequencing. For 9 genetic markers (c22-8, c29-2, L358, PK1, SAG2, SAG3, GRA6, BTUB, and Apico), the KI-1 and RH strains exhibited typical PCR-RFLP patterns identical to the type I strains. DNA sequencing of tandem repeats in 5 microsatellite markers (B17, B18, TUB2, W35, and TgM-A) of the KI-1 also revealed patterns characteristic of the type I. These results provide strong genetic evidence that KI-1 is a type I lineage of T. gondii.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.303-310
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• 2011

We characterized a cytoplasmic actin gene locus in greenling Hexagrammos otakii (Scorpaeniformes). Genomic clones isolated from the greenling DNA library contained two homologous cytoplasmic actin gene copies (HObact2.1 and HObact2.2) in a tail-to-head orientation. Their gene structure is characterized by six translated exons and one non-translated exon. Exon-intron organization and the nucleotide sequences of the two actin gene isoforms are very similar. However, only the HObact2.1 isoform contains microsatellite-like, dinucleotide repeats in the 5'-flanking region (named HOms2002) and intron 1 following the non-translated exon 1 (named HOms769). One microsatellite locus (HOms769) was highly polymorphic while the other (HOms2002) was not. Based on bioinformatic analysis, different transcription factor binding motifs are related to stress and immune responses in the two actin isoforms. Semiquantitative and real-time reverse transcription-PCR assays showed that both isoform transcripts were detectable ubiquitously in all the tissues examined. However, the basal expression levels of each isoform varied across tissues. Overall, the two isoforms showed a similar, but not identical, expression pattern. Our data suggest that the cytoplasmic actin genes may be the result of a recent duplication event in the greenling genome, which has not experienced significant subfunctionalization in their housekeeping roles.

• Childhood Kidney Diseases
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• v.12 no.1
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• pp.11-22
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• 2008

Telomeres consist of tandem guanine-thymine(G-T) repeats in most eukaryotic chromosomes. Human telomeres are predominantly linear, double stranded DNA as they ended in 30-200 nucleotides(bases,b) 3'-overhangs. In DNA replication, removal of the terminal RNA primer from the lagging strand results in a 3'-overhang of uncopied DNA. This is because of bidirectional DNA replication and specificity of unidirectional DNA polymerase. After the replication, parental and daughter DNA strands have unequal lengths due to a combination of the end-replication problem and end-processing events. The gradual chromosome shortening is observed in most somatic cells and eventually leads to cellular senescence. Telomere shortening could be a molecular clock that signals the replicative senescence. The shortening of telomeric ends of human chromosomes, leading to sudden growth arrest, triggers DNA instability as biological switches. In addition, telomere dysfunction may cause chronic allograft nephropathy or kidney cancers. The renal cell carcinoma(RCC) in women may be less aggressive and have less genomic instability than in man. Younger patients with telomere dysfunction are at a higher risk for RCC than older patients. Thus, telomeres maintain the integrity of the genome and are involved in cellular aging and cancer. By studying the telomeric DNA, we may characterize the genetic determinants in diseases and discover the tools in molecular medicine.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.101-106
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• 1998

The present study attempted to apply polymerase chain reaction (PCR) to develop a rapid differential diagnosis among Marek's disease, reticuloendotheliosis and avian leukosis. The primers chosen to detect Marek's disease virus (MDV) flank the 132bp tandem direct repeat of the MDV genome. The primers selected for reticuloendotheliosis virus (REV) and avian leukosis virus (ALV) are based on proviral long terminal repeats of spleen necrosis virus and Rous-associated virus-2 genomes, respectively. The specific PCR products of MDV, REV and ALV were observed with each primer and the reaction was not cross-reacted among the viruses. MDV-specific DNA was also amplified from the MDV-induced lymphoma (MDCC-MSB1) but not from the REV-induced tumor and ALV-induced lymphoma (LSCC-1104B1). In addition, proviral DNA of REV from REV-induced tumor and proviral DNA of ALV from ALV-induced lymphoma were also amplified by REV-specific and ALV-specific PCRs, respectively. Therefore these three PCR methods may be used to rapidly differentiate among MDV, REV and ALV-associated tumors in diagnosis.

• Tuberculosis and Respiratory Diseases
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• v.76 no.2
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• pp.59-65
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• 2014

Background: Variable-number tandem repeat (VNTR) typing is a promising method to discriminate the Mycobacterium tuberculosis isolates in molecular epidemiology. The purpose of this study is to determine the optimal VNTR combinations for discriminating isolated M. tuberculosis strains in Korea. Methods: A total of 317 clinical isolates collected throughout Korea were genotyped by using the IS6110 restriction fragment length polymorphism (RFLP), and then analysed for the number of VNTR copies from 32 VNTR loci. Results: The results of discriminatory power according to diverse combinations were as follows: 25 clusters in 83 strains were yielded from the internationally standardized 15 VNTR loci (Hunter-Gaston discriminatory index [HGDI], 0.9958), 25 clusters in 65 strains by using IS6110 RFLP (HGDI, 0.9977), 14 clusters in 32 strains in 12 hyper-variable VNTR loci (HGDI, 0.9995), 6 clusters in 13 strains in 32 VNTR loci (HDGI, 0.9998), and 7 clusters in 14 strains of both the 12 hyper-variable VNTR and IS6110 RFLP (HDGI, 0.9999). Conclusion: The combination of 12 hyper-variable VNTR typing can be an effective tool for genotyping Korean M. tuberculosis isolates where the Beijing strains are predominant.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.127-132
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• 2010

We have characterized full-length cDNA encoding Gall-6-tox protein, which was cloned from the fat body of the immunized Galleria mellonella larvae. The cloned cDNA of Gall-6-tox consists of 1301 nucleotides and contained an open reading frame of 891 nucleotides corresponding to a protein of 296 residues that includes a putative 16-residue signal sequence and a 280-residue mature peptide with a calculated mass of 30,707.73 Da. The deduced mature peptide contains conserved tandem repeats of six cysteine-stabilized alpha beta ($Cs{\alpha}{\beta}$) motifs, which was detected in scorpion toxins and insect defensins. In the sequence homology search, mature Gall-6-tox showed 34% and 28% amino acid sequence homology with Bomb-6-tox from Bombyx mori and Spod-11-tox from Spodoptera frugiperda, respectively. Gall-6-tox orthologs were only found in Lepidopteran species, indicating that this new immune-related gene family is specific to this insect order. RT-PCR analysis revealed that Gall-6-tox was expressed primarily in the larval fat bodies, hemocytes, and midgut against invading bacteria into hemocoel. Moreover, the expression time course of Gall-6-tox was examined up to 24 h in the fat bodies and midgut after injection of E. coli. Altogether, these results suggest that Gall-6-tox is derived from defensins and Gall-6-tox may play a critical role in Lepidoptera immune system.

• Journal of Microbiology
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• v.37 no.4
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• pp.234-242
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• 1999

To obtain the recombinant circumsporozoite (CS) protein for the diagnosis of patients and seroepidemiology of Plasmodium vivax malaria which have been prevalent in northern part of Kyonggido, the CS protein gene was amplified by the polymerase chain reaction (PCR) from genomic DNA of the Korean vivax malaria patient. The gene consists of 1,123 nucleotides except signal peptide sequences and had an uninterrupted reading frame encoding a protein of 374 amino acids with a central region of 20 tandem repeats of the nonapeptide. The CS protein gene was expressed in Escherichia coli and purified, the molecular weight of recombinant CS protein was about 44 kDa (monomer) under denaturing purification and about 65 kDa (dimer) under native purification by SDS-PAGE. The purified recombinant CS protein which has antigenicity to malaria patients in Western blot analysis and Enzyme-linked immunosorbent assay, reacted only with the serum of P. vivax (PV210) infected malaria patients with no cross reaction to the P. falciparum malaria patient. The recombinant CS protein purified in this study will serve as a useful antigen to support the diagnosis of malaria patients and seroepidemiology.

• Journal of Preventive Medicine and Public Health
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• v.45 no.1
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• pp.1-7
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• 2012

Using three Austrian case studies, the variegated applications of molecular typing in today's public health laboratories are discussed to help illustrate preventive management strategies relying on DNA subtyping. DNA macrorestriction analysis by pulsed field gel electrophoresis has become the gold standard for subtyping of food borne pathogens like listeria, salmonella, campylobacter and Bacillus cereus. Using a Salmonella Mbandaka outbreak from the year 2010 as example, it is shown how the comparison of patterns from human isolates, food isolates, animal isolates and feed isolates can allow to identify and confirm a source of disease. An epidemiological connection between the simultaneous occurrence of tuberculosis in cattle and deer with cases of human tuberculosis due to Mycobacterium caprae in 2010 was excluded using mycobacterial interspersed repetitive units variable-number tandem repeats subtyping. Also in 2010, multilocus sequence typing with nonselective housekeeping genes, the so-called sequence based typing protocol, was used to elucidate connections between an environmental source (a hospital drinking water system) and a case of legionellosis. During the last decades, molecular typing has evolved to become a routine tool in the daily work of public health laboratories. The challenge is now no longer to simply type microorganisms, but to type them in a way that allows for data exchange between public health laboratories all over the world.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8_spc
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• pp.1275-1283
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• 2019

Goats (Capra hircus) were domesticated during the late Neolithic, approximately 10,500 years ago, and humans exerted minor selection pressure until fairly recently. Probably the largest genetic change occurring over the millennia happened via natural selection and random genetic drift, the latter causing genes to be fixed in small and isolated populations. Recent human-influenced genetic changes have occurred through biometrics and genomics. For the most part, biometrics has concentrated upon the refining of estimates of heritabilities and genetic correlations. Heritabilities are instrumental in the calculation of estimated breeding values and genetic correlations are necessary in the construction of selection indices that account for changes in multiple traits under selection at one time. Early genomic studies focused upon microsatellite markers, which are short tandem repeats of nucleic acids and which are detected using polymerase chain reaction primers flanking the microsatellite. Microsatellite markers have been very important in parentage verification, which can impact genetic progress. Additionally, microsatellite markers have been a useful tool in assessing genetic diversity between and among breeds, which is important in the conservation of minor breeds. Single nucleotide polymorphisms are a new genomic tool that have refined classical BLUP methodology (biometric) to provide more accurate genomic estimated breeding values, provided a large reference population is available.