• 제목/요약/키워드: Novel mutation

검색결과 297건 처리시간 0.023초

대장균 K-12의 AcrAB/TolC Efflux Pump의 기능에 대한 MarB와 MarA의 추정적 억제조절 (Putative Negative Regulation of Novel MarB along with MarA upon the Function of AcrAB/TolC Efflux Pump of Escherichia coli K-12)

  • Byung-Tae Park
    • 대한의생명과학회지
    • /
    • 제5권1호
    • /
    • pp.27-40
    • /
    • 1999
  • 본 연구는 MarA와 함께 MarB가 AcrAB efflux pump를 목표로 하는지 여부, 그리고 항생제의 균체외 배출기능에 대하여 어떤 조절 작용이 있는지를 항생제 내성검사를 통하여 살펴보았다. 본 연구 결과는 MarB가 MarA와 함께 AcrAB/TolC efflux pump의 항생제 배출기 능을 억제적으로 조절한다는 것을 간접적으로 보여 주었으며, 한편 이미 알려진 대로 MarA는 acrRAB operon의 발현을 전사 수준에 서 positive regulation하므로, MarB는 AcrAB efflux pump의 기능을 억제적으로 조절한다는 것을 암시하고 있다. 그리고 MarA와 함께 MarB단백질의 작용 목표는 AcrAB efflux pump임을 간접적으로 보여주고 있다. 또한 MarB는 MarA와 함께 대장균의 다른 efflux system(들)의 항생제 배출기능에 대해서도 억제적으로 조절할 가능성이 높은 것으로 나타났다.

  • PDF

Screening of BRCA1/2 Mutations Using Direct Sequencing in Indonesian Familial Breast Cancer Cases

  • Anwar, Sumadi Lukman;Haryono, Samuel J;Aryandono, Teguh;Datasena, I Gusti Bagus
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권4호
    • /
    • pp.1987-1991
    • /
    • 2016
  • Breast cancer has emerged as the most prevalent cancer among women worldwide, including in Indonesia. The contribution of genes associated with high-risk breast-ovarian cancers, BRCA1 and BRCA2, in the Indonesian population is relatively unknown. We have characterized family history of patients with moderate- to high-risk of breast cancer predisposition in 26 unrelated cases from Indonesia for BRCA1/2 mutation analyses using direct sequencing. Known deleterious mutations were not found in either BRCA1 or BRCA2 genes. Seven variants in BRCA2 were documented in 10 of 26 patients (38%). All variants were categorized as unclassified (VUSs). Two synonymous variants, c.3623A>G and c.4035T>C, were found in 5 patients. One variant, c4600T>C, was found in a 38 year old woman with a family history of breast cancer. We have found 4 novel variants in BRCA2 gene including c.6718C>G, c.3281A>G, c.10176C>G, and c4490T>C in 4 unrelated patients, all of them having a positive family history of breast cancer. In accordance to other studies in Asian population, our study showed more frequent variants in BRCA2 compared to BRCA1. Further studies involving larger numbers of hereditary breast cancer patients are required to reveal contribution of BRCA1/2 mutations and/or other predisposing genes among familial breast cancer patients in Indonesia.

Cytogenetic and Genetic Mutation Features of de novo Acute Myeloid Leukemia in Elderly Chinese Patients

  • Su, Long;Li, Xian;Gao, Su-Jun;Yu, Ping;Liu, Xiao-Liang;Tan, Ye-Hui;Liu, Ying-Min
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권2호
    • /
    • pp.895-898
    • /
    • 2014
  • Objectives: The present study aimed to examine the cytogenetic and genetic mutation features of acute myeloid leukemia (AML) in elderly Chinese patients. Methods: A retrospective analysis of cytogenetics and genetic mutations was performed in 113 cases (age range 50-82 years) with de novo AML. Results: The most frequent cytogenetic abnormality was t (15;17) (q22;q21), detected in 10.0% (n = 9) of successfully analyzed cases, followed by t (8;21) (q22;q22) in 8.89% (n = 8), and complex karyotypes in 5.56% (n = 5). Those with complex karyotypes included 4 cases (4.44%) of monosomal karyotypes. The frequencies of NPM1, FLT3-ITD, c-kit, and CEBPA mutations were 27.4% (31/113), 14.5% (16/110), 5.88% (6/102), and 23.3% (7/30), respectively. The complete remission rates of patients in low, intermediate, and high risk groups were 37.5%, 48.6%, and 33.3%, respectively (${\chi}^2$ = 0.704, P = 0.703) based on risk stratification. Conclusion: Cytogenetics and genetic mutations alone may not be sufficient to evaluate the prognoses of elderly AML patients. The search for a novel model that would enable a more comprehensive evaluation of this population is therefore imperative.

Prevelance of Common YMDD Motif Mutations in Long Term Treated Chronic HBV Infections in a Turkish Population

  • Alagozlu, Hakan;Ozdemir, Ozturk;Koksal, Binnur;Yilmaz, Abdulkerim;Coskun, Mahmut
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권9호
    • /
    • pp.5489-5494
    • /
    • 2013
  • In the current study we aimed to show the common YMDD motif mutations in viral polymerase gene in chronic hepatitis B patients during lamivudine and adefovir therapy. Forty-one serum samples obtained from chronic hepatitis B patients (24 male, 17 female; age range: 34-68 years) were included in the study. HBV-DNA was extracted from the peripheral blood of the patients using an extraction kit (Invisorb, Instant Spin DNA/RNA Virus Mini Kit, Germany). A line probe assay and direct sequencing analyses (INNO-LIPA HBV DR v2; INNOGENETICS N.V, Ghent, Belgium) were applied to determine target mutations of the viral polymerase gene in positive HBV-DNA samples. A total of 41 mutations located in 21 different codons were detected in the current results. In 17 (41.5%) patients various point mutations were detected leading to lamivudin, adefovir and/or combined drug resistance. Wild polymerase gene profiles were detected in 24 (58.5%) HBV positive patients of the current cohort. Eight of the 17 samples (19.5%) having rtM204V/I/A missense transition and/or transversion point mutations and resistance to lamivudin. Six of the the mutated samples (14.6%) having rtL180M missense transversion mutation and resistance to combined adefovir and lamivudin. Three of the mutated samples (7.5%) having rtG215H by the double base substituation and resistance to adefovir. Three of the mutated samples (7.5%) having codon rtL181W due to the missense transversion point mutations and showed resistance to combined adefovir and lamivudin. Unreported novel point mutations were detected in the different codons of polymerase gene region in the current HBV positive cohort fromTurkish population. The current results provide evidence that rtL180M and rtM204V/I/A mutations of HBV-DNA may be associated with a poor antiviral response and HBV chronicity during conventional therapy in Turkish patients.

Neurofibromatosis type 1: a single center's experience in Korea

  • Kim, Min Jeong;Cheon, Chong Kun
    • Clinical and Experimental Pediatrics
    • /
    • 제57권9호
    • /
    • pp.410-415
    • /
    • 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.

타이로신 혈증 2례; 간암이 유발된 1례와 급성 간부전으로부터 회복된 1례의 비교 (Two Cases of Tyrosinemia; One with Hepatocellular Carcinoma and the other with Acute Liver Failure)

  • 김숙자;송웅주;전영미
    • 대한유전성대사질환학회지
    • /
    • 제13권1호
    • /
    • pp.48-53
    • /
    • 2013
  • Tyrosinemia I (fumarylacetoacetate hydrolase deficiency) is an autosomal recessive inborn error of tyrosine metabolism that produces liver failure in infancy or a more chronic course of liver disease with cirrhosis, often complicated by hepatocellular carcinoma in childhood or early adolescence. We studied a 37-year-old woman with tyrosinemia I whose severe liver disease in infancy and rickets during childhood were resolved with dietary therapy. From 14 years of age, she resumed unrestricted diet with the continued presence of the biochemical features of tyrosinemia, yet maintained normal liver function. In adult years, she accumulated only a small amount of succinylacetone. Despite this evolution to a mild biochemical and clinical phenotype, she eventually developed hepatocellular carcinoma. Her fumarylacetoacetate hydrolase genotype consists of a splice mutation, IVS6-1G>T, and a novel missense mutation, p.Q279R. Studies of resected liver revealed the absence of hydrolytic activity and immunological expression of fumarylacetoacetate hydrolase in tumour. In the non-tumoral areas, however, 53% of normal hydrolytic activity and immunologically present fumarylacetoacetate hydrolase were found. This case demonstrates the high risk of liver cancer in tyrosinemia I even in a seemingly favorable biological environment. In this study of tyrosinemia I, Case 2 with negative succinylacetone accumulation and the recovery of acute liver failure was compared with Case 1. Diet restriction and NTBC treatment are crucial to prevent hepatocellular carcinoma until liver transplant can take place and cure the condition. Further studies are needed to examine cases where liver cancer did not result despite clinical symptoms/signs of tyrosinemia type I.

  • PDF

암 유전자 배열에서 체세포 돌연변이 발견을 위한 유전자형 조사 시스템 (Genotype-Calling System for Somatic Mutation Discovery in Cancer Genome Sequence)

  • 박수영;정채영
    • 한국정보통신학회논문지
    • /
    • 제17권12호
    • /
    • pp.3009-3015
    • /
    • 2013
  • 차세대 시퀀싱(NGS)은 암에서 전사체 싱글 뉴클레오티드 변형 발견과 모든 지놈 발견을 가능하게 한다. 어느 한 위치에서 배열된 다수의 짧은 리드 시퀀스로부터 개인의 유전자형을 결정하는 가장 기초적인 방법이다. Byesian 알고리즘은 사후 유전자형 확률을 사용하여 파라미터 추정한다. 또 다른 방법인 EM 알고리즘은 최대 가능성 추정 방법을 사용해서 관측된 데이터에서 파라미터를 추정한다. 본 논문에서는 새로운 유전자형 조사 시스템을 제안하고 시퀀싱 에러 비율과 체세포 돌연 변이 상태 그리고 유전자형 확률의 사후 추정치에 관한 샘플 크기(S = 50, 100, 500)의 영향을 비교 분석하였다. 그 결과 작은 샘플 크기 50에서도 Byesian 알고리즘을 사용하여 추정한 파라미터가 EM 알고리즘 보다 더 정확하게 실제 파라미터에 근접하였다.

Recurrent thymic carcinoid tumor in familial isolated primary hyperparathyroidism

  • Song, Jeong Eun;Shon, Mu Hyun;Kim, Ga Young;Lee, Da Young;Lee, Jung Hun;Kim, Jong Ho;Shon, Ho Sang;Lee, Ji Hyun;Jeon, Eon Ju;Jung, Eui Dal
    • Journal of Yeungnam Medical Science
    • /
    • 제31권2호
    • /
    • pp.131-134
    • /
    • 2014
  • Familial isolated primary hyperparathyroidism(FIPH) is associated with multiple endocrine neoplasia type 1 (MEN1) syndrome, primary hyperparathyroidism accompanied by jaw-tumor syndrome, and familial hypocalciuric hypercalcemia. FIPH may be an early stage of MEN1 or an allelic variant of MEN1. Thymic carcinoid tumor is a rare tumor in MEN1 syndrome. Here, the authors report the case of a 40-year-old man diagnosed with recurrent thymic carcinoid tumor and FIPH. Both the patient and his elder sister had been previously diagnosed to have FIPH with a novel frameshift mutation in the MEN1 gene. Initially, the patient underwent thymectomy because of an incidental finding of a mediastinal mass in his chest X-ray, and had remained asymptomatic over the following 4 years. Pancreas computed tomography conducted to evaluate MEN1 syndrome revealed anterior and middle mediastinal masses, and resultantly, massive mass excision was performed. Histological findings disclosed atypical carcinoids with infiltrative margins. In view of the thymic carcinoid tumor relapse that occurred in this patient, the authors recommend that regular pancreas and pituitary imaging studies be conducted for FIPH associated with a MEN1 gene mutation.

Clinical and Molecular Features of Three Korean Cases of Activating Variants in the CASR Gene

  • Eun, Jung Kwan;Lee, Mi Sun;Lee, Ji Min;Lee, Eun Joo;Park, Sook-Hyun;Ko, Cheol Woo;Moon, Jung-Eun
    • Journal of Interdisciplinary Genomics
    • /
    • 제3권1호
    • /
    • pp.21-24
    • /
    • 2021
  • Purpose: Activating mutations of the calcium-sensing receptor (CASR) are a rare genetic disorder, and result in autosomal dominant hypocalcemia with hypercalciuria (ADHH). ADHH exhibited varying degrees of hypocalcemia. In this study, we report the clinical and molecular characteristics of activating variants in CASR patients diagnosed in Korea. Methods: This study included three patients with activating variants of CASR confirmed by biochemical and molecular analysis of CASR. Clinical and biochemical findings were reviewed chart retrospectively. Mutation analysis of CASR was performed by Sanger sequencing. Results: Subject 1 showed severe symptoms from the neonatal period and had difficulty in controlling the medications that were administered. Subject 2 was identified as having a novel variant of CASR with hypocalcemia and a low parathyroid hormone that were found in the neonatal period. During a course without medication, hypocalcemia occurred suddenly around 2 years of age. Subject 3 was diagnosed with hypoparathyroidism with hypocalcemic seizures starting from the neonatal period. About 4 years without taking medication with any symptom. However, at 10 years old revisited by repetitive hypocalcemic seizure events. Subject 1 and 3, were heterozygous for c.2474A>T (p.Y825F), c.2395G>A (p.E799K) located in the transmembrane domain (TMD) of CASR. Subject 2 was heterozygous for c.403A>C (S430L) located in the extracellular domain (ECD) of CASR. Conclusion: We reported 3 patients who have activating CASR variant with different onset and severity of symptoms. In the future, further study is needed to determine how the protein level according to the location of the mutation of CASR affects the degree of symptoms.

가족성 고콜레스테롤혈증의 스크린, 진단, 치료: 한국지질동맥경화학회 교육위원회 심포지엄 (Screening, Diagnosis, and Treatment of Familial Hypercholesterolemia: Symposium of the Education Committee, Korean Society of Lipid and Atherosclerosis)

  • 이찬주;이지현;최성훈;김신혜;강현재;이상학;박경수
    • 지질동맥경화학회지
    • /
    • 제7권2호
    • /
    • pp.122-154
    • /
    • 2018
  • Familial hypercholesterolemia (FH) is typically associated with single gene mutation that is inherited by autosomal dominant manner. Due to high cardiovascular risk, aggressive discovery, diagnosis, and treatment of FH are critical. Although FH is being increasingly spotlighted, we do not have sufficient data on Korean patients with FH. Here, we present the content of symposium of the Education Committee, Korean Society of Lipid and Atherosclerosis held in May 2018: 1) epidemiology, clinical diagnosis, Korean FH data, and regulation in Korea; 2) genes associated with FH, sequencing process in suspicious proband, cascade screening, and difficulty in genetic diagnosis in FH; 3) the importance of lipid-lowering therapy in FH, conventional and novel therapeutics for FH; 4) diagnosis of FH in children and adolescence, screening, and treatment of FH in children and adolescence; 5) history of FH studies in Korea, the structure and current status of FH registry of Korean Society of Lipid and Atherosclerosis; and 6) difficulty in diagnosis of heterozygous and homozygous FH, drug intolerance and achievement of treatment target. Discussion between speakers and panels were also added. We hope that this article is helpful for understanding FH and future studies performed in Korea.