• Journal of Genetic Medicine
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• v.7 no.1
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• pp.1-8
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• 2010

Hemophilia A is a sex-linked recessive coagulation disorder associated with diverse mutations of the factor VIII gene and a variety of phenotypes. The type of mutation involved dictates the activity of factor VIII, and in turn the severity of bleeding episodes and development of alloantibodies against factor VIII (inhibitors). Missense mutations are the most common genetic risk factors for hemophilia A, especially mild to moderate cases, but carry the lowest risk for inhibitor development. On the other hand, intron 22 inversion is the most common mutation associated with severe hemophilia A and is associated with high risk of inhibitor formation. Large deletions and nonsense mutations are also associated with high risk of inhibitor development. Additional mutations associated with hemophilia A include frameshift and splice site mutations. It is therefore valuable to assess the mutational backgrounds of hemophilia A patients in order to to interpret their symptoms and manage their health problems.

• Clinical and Experimental Pediatrics
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• v.57 no.9
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• pp.410-415
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• 2014

Purpose: Neurofibromatosis 1 (NF1) is an autosomal dominant condition caused by an NF1 gene mutation. NF1 is also a multisystem disorder that primarily affects the skin and nervous system. The goal of this study was to delineate the phenotypic characterization and assess the NF1 mutational spectrum in patients with NF1. Methods: A total of 42 patients, 14 females and 28 males, were enrolled in this study. Clinical manifestations and results of the genetic study were retrospectively reviewed. Results: Age of the patients at the time of NF1 diagnosis was $15.8{\pm}14.6$ years (range, 1-62 years). Twelve patients (28.6%) had a family history of NF1. Among the 42 patients, $Caf\acute{e}$-au-lait spots were shown in 42 (100%), neurofibroma in 31 (73.8%), freckling in 22 (52.4%), and Lisch nodules in seven (16.7%). The most common abnormal finding in the brain was hamartoma (20%). Mental retardation was observed in five patients (11.9%), seizures in one patient (2.4%), and plexiform neurofibromas (PNFs) in four patients (9.5%). One patient with PNFs died due to a malignant peripheral nerve sheath tumor in the chest cavity. Genetic analysis of seven patients identified six single base substitutions (three missense and three nonsense) and one small deletion. Among these mutations, five (71.4%) were novel (two missense mutations: p.Leu1773Pro, p.His1170Leu; two nonsense mutations: $p.Arg2517^*$, $p.Cys2371^*$; one small deletion: $p.Leu1944Phefs^*6$). Conclusion: The clinical characteristics of 42 Korean patients with NF1 were extremely variable and the mutations of the NF1 gene were genetically heterogeneous with a high mutation-detection rate.

• Journal of Genetic Medicine
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• v.9 no.2
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• pp.98-100
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• 2012

Holt-Oram syndrome (HOS) is the most common heart-hand syndrome, which is inherited in an autosomal dominant manner, but most cases are sporadic. This condition is characterized by upper-extremity malformations involving radial-ray, thenar, and carpal bones, and congenital heart malformations including atrial septal defect and ventricular septal defect. It is caused by mutations in the TBX5 gene. In this report, a Korean case with HOS is described, which is inherited from her father. A novel nonsense mutation, $p.Glu294^*$, was identified. This is the first Korean case with HOS confirmed by genetic testing.

• Journal of Chest Surgery
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• v.50 no.5
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• pp.386-390
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• 2017

$Birt-Hogg-Dub{\acute{e}}$ syndrome (BHDS) is a rare disease with autosomal dominant inheritance that manifests through skin tumors, pulmonary cystic lesions, and renal tumors. A mutation of FLCN located on chromosome 17p11.2, which encodes a tumor-suppressor protein (folliculin), is responsible for the development of BHDS. We report the case of a patient presenting with spontaneous pneumothorax, in whom a familial genetic study revealed a novel nonsense mutation: $p.(Arg379^*)$ in FLCN.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.3
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• pp.157-162
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• 2003

Our earlier studies found a significant correlation between the activities of ranitidine N-oxidation catalyzed by hepatic flavin-containing monooxygenase (FMO) and the presence of mutations in exon 4 (E158K) and exon 7 (E308G) of the FMO3 gene in Korean volunteers. However, caffeine N-1 demethylation (which is also partially catalyzed by FMO) was not significantly correlated with these FMO3 mutations. In this study, we examined another common mutation (V257M) in exon 6 of FMO3 gene. The V257M variant, which is caused by a point mutation (G769A), was commonly observed (13.21% allele frequency) in our subjects (n=159). This point mutation causes a substitution of $Val^{257}$ to $Met^{257}$, with transformation of the secondary structure. The presence of this mutant allele correlated significantly with a reduction in caffeine N-1-demethylating activity, but was not correlated with the activity of N-oxidation of ranitidine. In a family study, the low FMO activity observed in a person heterozygous for a nonsense mutation in exon 4 (G148X) and heterozygous for missense mutation in exon 6 (V257M) of FMO3 was attributed to the mutations. Our results suggest that various point mutations in the coding regions of FMO3 may influence FMO3 activity according to the probe substrates of varying chemical structure that correlate with each mutation on the FMO3 gene.

• Molecules and Cells
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• v.20 no.3
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.

• Molecular & Cellular Toxicology
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• v.3 no.4
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• pp.262-266
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• 2007

ENPP2, a 125 kDa secreted lysophopholipase D which originally identified as a tumor-motogen, Autotaxin, enhances cellular locomotion, cell proliferation, angiogenesis and cell survival by generating the signal molecule lysophosphatic acid or sphingosine-1-phosphate. Previous studies have suggested that expression of Autotaxin is associated with invasive phenotype in advanced breast carcinomas. Thus, to determine whether genetic alterations of ENPP2 gene are involved in the development or progression of breast cancer, we analyzed its somatic mutation in 85 breast carcinomas by single-stranded conformational polymorphism and sequencing. Overall, six ENPP2 mutations were found (7.0%), comprising five missense and one nonsense mutation (s). To our knowledge, this is the first report on ENPP2 mutation in breast carcinoma, and the data indicate that ENPP2 is occasionally mutated in breast carcinomas, and suggest that ENPP2 mutation may contribute to the tumor development in some breast carcinomas.

• Tuberculosis and Respiratory Diseases
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• v.50 no.1
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• pp.94-105
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• 2001

Background : Examining the biological susceptibility of Mycobacterium tuberculosis to pyrazinamide (PZA) in vitro is very difficult as PZA is inactive under normal culture conditions. The biological susceptibility test, an enzyme assay for Pzase activity, and a genetic test for pncA gene mutations, were performed in order to predict PZA resistance. Methods : 28 cultured clinical isolates of Mycobacterium tuberculosis were tested. The biological susceptibility was performed by the absolute concentration method using Lowenstein-Jensen media. The PZase activity was tested by means of Wayne's method. A 710-bp region includes the entire open reading frame of pncA was amplified and sequenced. Results : All six strains with positive PZase activity exhibited no pncA mutations with one strain showing a false resistance in the biological susceptibility test. Among the 22 strains with no PZase activity, 21 exhibited showed pncA mutations. In the biological susceptibility test, 20 strains were resistant, and one was susceptible, and the other flied to test. The mutation types varied with ten missense, one silent and one nonsense mutation 1 slipped-strand mispairing, and 6 frameshift mutations. Three strains had an adenine to guanine mutation at position -11 upstream of the start codon. Conclusion : The mutation at the pncA promotor region is frequent at -11 upstream position. Automatic sequencing of pncA is a useful tool for rapid and accurate detection of PZA resistant M. tuberculosis, and for demonstrating the epidemiological relatedness of the PZA resistant M. tuberculosis strains.

• Journal of Gynecologic Oncology
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• v.29 no.6
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• pp.90.1-90.12
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• 2018

Objective: We performed small-scale mutation and large genomic rearrangement (LGR) analysis of BRCA1/2 in ovarian cancer patients to determine the prevalence and the characteristics of the mutations. Methods: All ovarian cancer patients who visited a single institution between September 2015 and April 2017 were included. Sanger sequencing, multiplex ligation-dependent probe amplification (MLPA), and long-range polymerase chain reaction (PCR) were performed to comprehensively study BRCA1/2. The genetic risk models BRCAPRO, Myriad, and BOADICEA were used to evaluate the mutation analysis. Results: In total, 131 patients were enrolled. Of the 131 patients, Sanger sequencing identified 16 different BRCA1/2 small-scale mutations in 20 patients (15.3%). Two novel nonsense mutations were detected in 2 patients with a serous borderline tumor and a large-cell neuroendocrine carcinoma. MLPA analysis of BRCA1/2 in Sanger-negative patients revealed 2 LGRs. The LGRs accounted for 14.3% of all identified BRCA1 mutations, and the prevalence of LGRs identified in this study was 1.8% in 111 Sanger-negative patients. The genetic risk models showed statistically significant differences between mutation carriers and non-carriers. The 2 patients with LGRs had at least one blood relative with breast or ovarian cancer. Conclusion: Twenty-two (16.8%) of the unselected ovarian cancer patients had BRCA1/2 mutations that were detected through comprehensive BRCA1/2 genetic testing. Ovarian cancer patients with Sanger-negative results should be considered for LGR detection if they have one blood relative with breast or ovarian cancer. The detection of more BRCA1/2 mutations in patients is important for efforts to provide targeted therapy to ovarian cancer patients.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.6 no.1
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• pp.58-62
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• 2006

Gaucher disease is an inherited disorder due to a deficiency in the activity of glucocerebrosidase (EC. 3.2.1.45) by genetic mutation which resulted from missense, nonsense, frameshift, deletion in long arm 21 of chromosome 1 (1q21). Gaucher disease is classified into the main three types as type 1 (nonneuronopathic), type 2 (acute neuronopathic) and type 3 (subacute neuronopathic) according to the progressive phase of manifestations and nervous system involvement. Gaucher disease patients had been treated by using the method as splenectomy and bone marrow transplantation. But enzyme replacement therapy as a more effective treatment has been available since the early 1990's. In order to treat Gaucher disease efficiently by using ERT, it is necessary to chase the progress of the therapy. In this study, therefore, we tried to chase the progress of the ERT by using the measurement of chitotriosidase activity in Gaucher disease patients.