Karyotype Analysis and Physical Mapping Using Two rRNA Genes in Dioecious Plant, Humulus japonicus Sieboid & Zucc

Kim, Soo-Young,Kim, Chan-Soo,Lee, Joongku,Bang, Jae-Wook Korean Society of Genetics 2008 Genes & Genomics Vol.30 No.2

Using meiosis and mitosis chromosomes, we have karyotyped and physically mapped of Humulus japonicus. The somatic metaphase chromosome numbers were 2n = 2x = 14 + XX in female, 2n = 2x = 14 + XY<SUB>1</SUB>Y<SUB>2</SUB> in male and 2n = 3x = 21 + XXX in triploid. The 5S and 45S rDNA genes were physically mapped on the metaphase chromosomes using fluorescence in situ hybridization (FISH). One pair of 5S rDNA gene was detected on the short arm of chromosome 4 and two pairs of 45S rDNA gene were observed on the terminal regions of the short arms of chromosome 5 and 7 in both female and male plants. In addition, three pairs of two rDNAs were detected on the chromosome 4, 5 and 7 of triploid. At meiosis, a trivalent chromosome figure was clearly seen, of which Y<SUB>1</SUB> and Y<SUB>2</SUB> could be distinguished from X by their premature condensation and three chromosomes, Y<SUB>1</SUB>-X-Y<SUB>2</SUB>, the forms associated by terminal chiasmata.

Overexpression of Hoxc8, a Homeobox Gene, in B16F10 Melanoma Inhibits the Growth of Tumor Cells

Kim, Byung-Gyu,Park, Hyoung Woo,Park, Kyung Ah,Kim, Myoung Hee Korean Society of Genetics 2008 Genes & Genomics Vol.30 No.2

Homeobox (Hox)-containing genes have been identified as regulators which control the expression of a variety of genes involved in development and differentiation. Recent reports also suggested an involvement of Hox genes in transformation and/or tumor progression. In human prostate cancer, overexpression of HOXC8 was associated with a loss of tumor differentiation, which implies the involvement of HOXC8 in the process leading to the tumorigenicity of tumor cells. In order to investigate the role of Hoxc8 in the growth of tumor cells, Hoxc8 was designed to be expressed constitutively in B16F10 melanoma cells after stable transfection, and then a clone B16F10Shoxc8#14 overexpressing Hoxc8 was selected and analyzed further. B16F10Shoxc8#14 expressed Hoxc8 at high level and exhibited a reduced growth rate in vitro. When the cell cycle progress was analyzed, it has a decreased S phase population through upregulation of cell cycle regulators, such as p21, HDAC8 and E2F5. When the effect of Hoxc8 was analyzed on tumor growth in vivo C57BL/6 mice, the tumorigenicity as well as the growth rate was significantly decreased, indicating that the overexpression of Hoxc8 in B16F10 melanoma inhibits the tumor proliferation, probably functioning as a cell cycle regulator.

The Adenylyl Cyclase Encoded by rutabaga Is Required for Larval Molting in Drosophila

Son, Wonseok,Han, Pyung-Lim,Chung, Yun Doo Korean Society of Genetics 2008 Genes & Genomics Vol.30 No.2

Hormonal control of insect growth and metamorphosis by neuroendocrine system is well established, yet the cellular mechanism underlying the synthesis and release of insect hormones is not clearly understood. Here we report that a novel enhancer detection line, rut<SUP>lethal-1096</SUP>, failed to molt from second to third instar larvae, thus showing a lethal phenotype. Molecular cloning indicated that the enhancer detector was inserted in the proximal promoter region of the rut-encoded adenylyl cyclase (AC) gene. Similarly, the known rut alleles, rut<SUP>1</SUP> and rut<SUP>1084</SUP>, were also found to be affected mildly in their larval and pupal development. The enriched expression of the reporter gene lacZ was detected in the ring gland that is an insect larval glandular organ secreting various hormones involved in ecdysis. Taken together, our data suggest the rut-encoded AC plays a vital role in larval molting, probably by regulating the function of ring glands.

The A190T Variation in Human Polycystin 2, Previously Known as a Missense Mutation, is a Nonsynonymous cSNP in Korean Population

Park, Mi-Hyun,Kim, Hye-Kyung,Kim, Jin-Man,Lee, Byung-Ho,Chang, Mi-He,Lee, Me-Yae,Kim, Hyeon-Jin,Lee, Jong-Young,Hong, Seong-Chool Korean Society of Genetics 2008 Genes & Genomics Vol.30 No.2

Polycystin 2 (PKD2) is an ion channel that regulates the intracellular calcium ion concentration. Amino acid changes in PKD2 are known to cause autosomal dominant polycystic kidney disease(ADPKD), and are possibly associated with many other complex diseases. In an effort to find cSNPs (single nucleotide polymorphisms within cDNA sequence) in PKD2, we used direct sequencing analysis to screen the entire coding region of the PKD2 gene. We identified a major nonsynonymous cSNP, Ala190Thr (A190T), in the N-terminal intracellular domain of PKD2. This nonsynonymous cSNP was previously reported as a mutation for ADPKD. However, this study excluded the possibility that the A190T variation was a missense mutation for ADPKD by a thorough clinical evaluation and population study. In 500 genetically unrelated Koreans, the allele frequencies of G and A at the A190T variation were 64% and 36%, respectively. The genotype frequency of the cSNP was not deviated from Hardy-Weinberg equilibrium. These experimental results indicate that mutational research needs to be confirmed by a thorough clinical evaluation and population study. Furthermore, the A190T variation is implicated as having possible causative roles in the pathogenesis of various ADPKD-related diseases. Intensive population studies should be conducted to address the etiological role of the A190T variation in these ADPKD-related diseases.

Characterization and comparative expression analysis of CUL1 genes in rice

Kim, Sang-Hoon,Woo, Og-Geum,Jang, Hyunsoo,Lee, Jae-Hoon Korean Society of Genetics 2018 Genes & Genomics Vol.40 No.3

<P>Cullin-RING E3 ubiquitin ligase (CRL) complex is known as the largest family of E3 ligases. The most widely characterized CRL, SCF complex (CRL1), utilizes CUL1 as a scaffold protein to assemble the complex components. To better understand CRL1-mediated cellular processes in rice, three CUL1 genes (OsCUL1s) were isolated in Oryza sativa. Although all OsCUL1 proteins exhibited high levels of amino acid similarities with each other, OsCUL1-3 had a somewhat distinct structure from OsCUL1-1 and OsCUL1-2. Basal expression levels of OsCUL1-3 were much lower than those of OsCUL1-1 and OsCUL1-2 in all selected samples, showing that OsCUL1-1 and OsCUL1-2 play predominant roles relative to OsCUL1-3 in rice. OsCUL1-1 and OsCUL1-2 genes were commonly upregulated in dry seeds and by ABA and salt/drought stresses, implying their involvement in ABA-mediated processes. These genes also showed similar expression patterns in response to various hormones and abiotic stresses, alluding to their functional redundancy. Expression of the OsCUL1-3 gene was also induced in dry seeds and by ABA-related salt and drought stresses, implying their participation in ABA responses. However, its expression pattern in response to hormones and abiotic stresses was somehow different from those of the OsCUL1-1 and OsCUL1-2 genes. Taken together, these findings suggest that the biological role and function of OsCUL1-3 may be distinct from those of OsCUL1-1 and OsCUL1-2. The results of expression analysis of OsCUL1 genes in this study will serve as a useful platform to better understand overlapping and distinct roles of OsCUL1 proteins and CRL1-mediated cellular processes in rice plants.</P>

Targeted next-generation sequencing for identifying genes related to horse temperament

Song, Soyoung,Oh, Dong-Yep,Cho, Gil-Jae,Kim, Dong Hee,Park, Yong-Soo,Han, Kyudong Korean Society of Genetics 2017 Genes & Genomics Vol.39 No.12

<P> It is a fundamental challenge to discover the association of genetic traits with phenotypic traits. In this study, we aimed to identify possible genetic traits related to horse temperament. Based on previous findings, we selected 71 candidate genes related to temperamental trait and examined them in the human and horse reference genomes (hg38 and equCab2, respectively). We found 16 orthologous genes and, by comparing with the human reference genome, 17 homologous genes in the horse reference genome. We designed probes specific for the 33 horse genes. Using the probes, we built sequencing libraries of the genomic DNA samples from eight aggressive and eight docile horses, and sequenced the constructed libraries using the Illumina Hiseq2500 platform. Through the analysis of the targeted exome sequences, we identified single nucleotide polymorphisms (SNPs) in the genes. SNPs could be served as genetic markers to evaluate aggressive or docile levels of horses. To examine whether any genetic variants are associated with horse temperament, we performed genome-wide association study (GWAS) using the SNP data. GWAS analysis identified ten variants (p-value <0.05) which could be related to horse temperament. We validated the variants using Sanger sequencing. The most significant variants were found in MAOA (c.1164+41T>C) and AR (c.1047+27G>T) genes with 8.09 × 10<SUP>-4</SUP> p-value. We suggest that the variants might be used to assess horse temperament and to determine superior horses for riding or racing. </P>

Molecular Study of X-Chromosome Mosaicism in Turner Syndrome Patients using DNAs Extracted from Archives Cytogenetic Slides

Cho, Eun-Hee,Kim, Jin-Woo,Kim, Young-Mi,Ryu, Hyun-Mee,Park, So-Yeon Korean Society of Medical Genetics 1999 대한의학유전학회지 Vol.3 No.1

To study the X chromesome mosaicism in the cytogenetically pure 45,X Turner syndrome patients, we applied PCR technique using DNAs extracted from archived cytogenetic slides. We amplified the DNAs using nested primers targeted to a highly polymorphic short tandem repeat(STR) of the human androgen receptor gene(HUMARA) for the detection of X chromosome mosaicism. This assay is a very sensitive and useful method which can be applied to the DNAs extracted from archived cytogenetic slides to detect X mosaicism. We have tested 50 normal Korean females to determine whether the HUMARA locus is highly polymorphic among Koreans. 85% of Korean population showed heterozygosity in the HUMARA locus. We analysed the 24 DNAs extracted from archived slides of patients and abortuses with Turner syndrome in cytogenetic analysis. We observed the heterozygosities of 50% from pure 45,X patients, 83% from the patients with mosaic Turner syndrome and 8.3% from the abortuses of pure 45,X. Using the PCR technique of the HUMARA locus in the archived cytogenetic slides, we detected X chromosome mosaicism which could not be detected in cytogenetic analysis.

Association analysis of a polymorphism of the angiotensin I-converting enzyme gene and angiotensin II Type 1 receptor gene in Korean population

Yang, Young-Mok,Park, Jong-Hwan,Lee, Hyun-Young,Moon, Eon-Soo Korean Society of Medical Genetics 1998 대한의학유전학회지 Vol.2 No.1

Previously, we made a study report on the genotype distribution and the gene frequency of angiotesin I-converting enzyme (ACE) in Korean population, and on the association between hypertension and genetic variance of ACE. This time, we have investigated a rapid mismatch-PCR/RFLP assays for the variant of the angiotesin II type 1 receptor ($AT_1R$) gene (an $A{\rightarrow}C$ transversion at position 1166 of $AT_1R$ gene), a mutation which may interact with the ACE polymorphism in the determining of risk of myocardial infarction. The genotype distributions of Koreans' angiotensin II type 1 receptor gene were AA (66.3%):AC (28.1%):CC (5.6%), thus the AA genotype was most numerous, and the allele frequency was A:C = 0.803:0.197. Genotype distributions were shown as AA (76.8%):AC (20.9%):CC (2.3%), the allele frequency was A:C = 0.872:0.128 in the male group, and AA (47.4%):AC (41.0%):CC (11.6%), A:C = 0.679:0.321 in the female group. Differences were highly significant between the male and female groups (p<0.0001). Genotype distributions between angiotensin II type 1 receptor gene and angiotensin converting enzyme gene showed that there is no significance between $AT_1R$ genotypes and ACE genotypes in total subjects (p>0.05).

A case of maternal uniparental disomy of chromosome 20 detected by noninvasive prenatal test of 1,000 high-risk pregnancies

Cha, Dong Hyun,Lee, Junnam,Jeon, Young-Joo,Jung, Yong Wook,Jang, Ja-Hyun,Lee, Taeheon,Cho, Eun Hae Korean Society of Medical Genetics and Genomics 2017 대한의학유전학회지 Vol.14 No.1

Chromosomal loss in trisomy (trisomy rescue) to generate a disomic fetus can cause confined placental mosaicism and/or feto/placental mosaicism. After trisomy rescue event, there is a risk of fetal uniparental disomy (UPD). Noninvasive prenatal test (NIPT) reflects the genomic constitution of the placenta, not of the fetus itself. Feto-placental discrepancy can therefore cause false-positive (trisomy) NIPT results. These discordant NIPT results can serve as important clues to find UPD associated with confined placental mosaicism. We report a case with maternal UPD of chromosome 20, detected by NIPT of 1,000 high-risk pregnancies, carried out for detecting chromosomal abnormalities in Koreans.

A case of Mowat-Wilson syndrome with developmental delays and Hirschsprung's disease

Lee, Darae,Kim, Ja Hye,Cho, Ja Hyang,Oh, Moon-Yun,Lee, Beom Hee,Kim, Gu-Hwan,Choi, Jin-Ho,Yoo, Han-Wook Korean Society of Medical Genetics and Genomics 2014 대한의학유전학회지 Vol.11 No.2

Mowat-Wilson syndrome is an extremely rare genetic disease that is characterized by intellectual disability, facial dysmorphism, Hirschsprung's disease, and other congenital anomalies. This disorder is caused by heterozygous mutations or deletions in the zinc finger E-box-binding homeobox-2 gene (ZEB2). Thus far, approximately 200 cases of Mowat-Wilson syndrome have been reported worldwide. In Korea, only one case with a 2q22 deletion, which also affects ZEB2, has been previously reported. Here, we describe a patient with Mowat-Wilson syndrome who presented with developmental delays, typical facial dysmorphism, and Hirschsprung's disease. Molecular analysis of ZEB2 identified a novel heterozygous mutation at c.190dup ($p.S64Kfs^*6$). To our knowledge, this is the second report of a Korean patient with Mowat-Wilson syndrome that has been confirmed genetically.