• 제목/요약/키워드: direct sequencing

검색결과 307건 처리시간 0.029초

An overview of current knowledge about cell-free RNA in amniotic fluid

  • Jung, Yong Wook;Shin, Yun Jeong;Shim, Sung Han;Cha, Dong Hyun
    • Journal of Genetic Medicine
    • /
    • 제13권2호
    • /
    • pp.65-71
    • /
    • 2016
  • Cell-free nucleic acids (cf-NAs) originate in trophoblasts and are detected in the maternal plasma. Using innovative bioinformatic technologies such as next-generation sequencing, cf-NAs in the maternal plasma have been rapidly applied in prenatal genetic screening for fetal aneuploidy. Amniotic fluid is a complex and dynamic fluid that provides growth factors and protection to the fetus. In 2001, the presence of cf-NA in amniotic fluid was reported. Amniotic fluid is in direct contact with the fetus and is derived from fetal urine and maternal and fetal plasma. Therefore, these genetic materials have been suggested to reflect fetal health and provide real-time genetic information regarding fetal development. Recently, several studies evaluated the global gene expression changes of amniotic fluid cell-free RNA according to gestational age. In addition, by analyzing the transcriptome in the amniotic fluid of fetal aneuploidy, potential key pathways and novel biomarkers for fetal chromosomal aneuploidy were identified. Here, we review the current knowledge of cell-free RNA in amniotic fluid and suggest future research directions.

Relative Effect of Glyphosate on Glyphosate-Tolerant Maize Rhizobacterial Communities is Not Altered by Soil Properties

  • Barriuso, Jorge;Mellado, Rafael P.
    • Journal of Microbiology and Biotechnology
    • /
    • 제22권2호
    • /
    • pp.159-165
    • /
    • 2012
  • The rhizobacterial composition varies according to the soil properties. To test if the effect of herbicides on the rhizobacterial communities of genetically modified NK603 glyphosate-tolerant maize varies according to different soil locations, a comparison was made between the effects of glyphosate (Roundup Plus), a post-emergence applied herbicide, and a pre-emergence applied herbicide (GTZ) versus untreated soil. The potential effect was monitored by direct amplification, cloning, and sequencing of the soil DNA encoding 16S rRNA, and high-throughput DNA pyrosequencing of the bacterial DNA coding for the 16S rRNA hypervariable V6 region. The results obtained using three different methods to analyze the herbicide effect on the rhizobacterial communities of genetically modified NK603 maize were comparable to those previously obtained when glyphosate-tolerant maize was grown in soil with different characteristics. Both herbicides decreased the bacterial diversity in the rhizosphere, with Actinobacteria being the taxonomic group most affected. The results suggest that both herbicides affected the structure of the maize rhizobacterial community, but glyphosate was environmentally less aggressive.

Possible Epithelial Ovarian Cancer Association with HPV18 or HPV33 Infection

  • Zhang, Pei-Pei;Zhou, Lei;Cao, Jia-Shi;Li, Yi-Ping;Zeng, Zhi;Sun, Ni;Shen, Li;Zhu, Hao-Yue;Ruan, Yang;Zha, Wen-Ting;Wang, Xin-Yu;Zhang, Ke-Qiang;Zhang, Ran
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권6호
    • /
    • pp.2959-2964
    • /
    • 2016
  • The present study was conducted to investigate the prevalence of HPV infection in epithelial ovarian cancer (EOC) in Hunan province. DNA samples were collected from paraffin embedded ovarian tissue from 322 patients with EOC, 99 with ovarian benign tumors and 199 normal persons. The polymerase chain reaction and direct sequencing were used to identify the HPV types in the samples. The relationship between the infection of human papillomavirus (HPV) and the epithelial ovarian carcinoma (EOC) was investigated combined with clinical data. The prevalence of HPV18 and HPV33 in EOC group and benign group was higher than in the normal group. HPV18 and HPV33 may play a role in the development of both EOC and ovarian benign tumor and may participate in the development of EOC with traditional risk factors, family history and abortion, possibly exerting synergistic effects.

Genetic Identification of Spirometra erinaceieuropaei Spargana in Liaoning and Hubei Provinces, PR China

  • He, Li;Fang, Zheng-Ming;Xue, Ting;Zhang, Er-Fu;An, Chun-Li
    • Parasites, Hosts and Diseases
    • /
    • 제57권3호
    • /
    • pp.309-312
    • /
    • 2019
  • Spargana were collected from human and frogs in Liaoning and Hubei Provinces, China. PCR amplification and direct sequencing of A cox1 fragment was PCR-amplified from genomic DNA extracted from 7 specimens (5 from humans and 2 from frogs). The cox1 fragment (390 bp) showed 97-100% similarity to the reference sequence of S. erinaceieuropaei and 88-89% to the reference sequence of S. decipiens. There were 1-12 bases different between these worms, but no obvious genetic variation (0-3.3%) to the references. There was little difference of cox1 gene between sparganum samples of humans and frogs (1-3%). This study is the first report on S. erinaceieuropaei spargana from humans in Liaoning and Hubei Provinces.

Discrepancies between Mitochondrial DNA and AFLP Genetic Variation among Lineages of Sea Slaters Ligia in the East Asian Region

  • Kang, Seunghyun;Jung, Jongwoo
    • Animal Systematics, Evolution and Diversity
    • /
    • 제36권4호
    • /
    • pp.347-353
    • /
    • 2020
  • Although sea slaters Ligia have a significant role in rocky shore habitats, their taxonomic entities have not been clearly understood. In this study, we investigated whether genetic variation inferred from a nuclear genetic marker, namely amplified fragment length polymorphism (AFLP), would conform to that of a mitochondrial DNA marker. Using both the mitochondrial DNA marker and the AFLP marker amplified by the six selective primer sets, we analyzed 95 Ligia individuals from eight locations from East Asia. The direct sequencing of mitochondrial 16S rRNA gene revealed three distinct genetic lineages, with 9.8-11.7 Kimura 2-parameter genetic distance. However, the results of AFLP genotyping analysis with 691 loci did not support those of mitochondrial DNA, and revealed an unexpectedly high proportion of shared polymorphisms among lineages. The inconsistency between the two different genetic markers may be explained by difference in DNA evolutionary history, for example inheritance patterns, effective population size, and mutation rate. The other factor is a possible genomic island of speciation, in that most of the genomic parts are shared among lineages, and only a few genomic regions have diverged.

Epigenetic Silencing of CHOP Expression by the Histone Methyltransferase EHMT1 Regulates Apoptosis in Colorectal Cancer Cells

  • Kim, Kwangho;Ryu, Tae Young;Lee, Jinkwon;Son, Mi-Young;Kim, Dae-Soo;Kim, Sang Kyum;Cho, Hyun-Soo
    • Molecules and Cells
    • /
    • 제45권9호
    • /
    • pp.622-630
    • /
    • 2022
  • Colorectal cancer (CRC) has a high mortality rate among cancers worldwide. To reduce this mortality rate, chemotherapy (5-fluorouracil, oxaliplatin, and irinotecan) or targeted therapy (bevacizumab, cetuximab, and panitumumab) has been used to treat CRC. However, due to various side effects and poor responses to CRC treatment, novel therapeutic targets for drug development are needed. In this study, we identified the overexpression of EHMT1 in CRC using RNA sequencing (RNA-seq) data derived from TCGA, and we observed that knocking down EHMT1 expression suppressed cell growth by inducing cell apoptosis in CRC cell lines. In Gene Ontology (GO) term analysis using RNA-seq data, apoptosis-related terms were enriched after EHMT1 knockdown. Moreover, we identified the CHOP gene as a direct target of EHMT1 using a ChIP (chromatin immunoprecipitation) assay with an anti-histone 3 lysine 9 dimethylation (H3K9me2) antibody. Finally, after cotransfection with siEHMT1 and siCHOP, we again confirmed that CHOP-mediated cell apoptosis was induced by EHMT1 knockdown. Our findings reveal that EHMT1 plays a key role in regulating CRC cell apoptosis, suggesting that EHMT1 may be a therapeutic target for the development of cancer inhibitors.

Human Papillomavirus Genotype Distribution and E6/E7 Oncogene Expression in Turkish Women with Cervical Cytological Findings

  • Tezcan, Seda;Ozgur, Didem;Ulger, Mahmut;Aslan, Gonul;Gurses, Iclal;Serin, Mehmet Sami;Giray, Burcu Gurer;Dilek, Saffet;Emekdas, Gurol
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권9호
    • /
    • pp.3997-4003
    • /
    • 2014
  • Background: Infection with certain human papillomavirus (HPV) genotypes is the most important risk factor related with cervical cancer. The objective of the present study was to investigate the prevalence of HPV infection, the distribution of HPV genotypes and HPV E6/E7 oncogene mRNA expression in Turkish women with different cervical cytological findings in Mersin province, Southern Turkey. Materials and Methods: A total of 476 cytological samples belonging to women with normal and abnormal cervical Pap smears were enrolled in the study. For the detection and genotyping assay, a PCR/direct cycle sequencing approach was used. E6/E7 mRNA expression of HPV-16, 18, 31, 33, and 45 was determined by type-specific real-time NASBA assay (NucliSENS EasyQ$^{(R)}$HPV v1.1). Results: Of the 476 samples, 106 (22.3%) were found to be positive for HPV DNA by PCR. The presence of HPV was significantly more common (p<0.001) in HSIL (6/8, 75%) when compared with LSIL (6/14, 42.9%), ASC-US (22/74, 29.7%) and normal cytology (72/380, 18.9%). The most prevalent genotypes were, in descending order of frequency, HPV genotype 66 (22.6%), 16 (20.8%), 6 (14.2%), 31 (11.3%), 53 (5.7%), and 83 (4.7%). HPV E6/E7 oncogene mRNA positivity (12/476, 2.5%) was lower than DNA positivity (38/476, 7.9%). Conclusions: Our data present a wide distribution of HPV genotypes in the analyzed population. HPV genotypes 66, 16, 6, 31, 53 and 83 were the predominant types and most of them were potential carcinogenic types. Because of the differences between HPV E6/E7 mRNA and DNA positivity, further studies are required to test the role of mRNA testing in the triage of women with abnormal cervical cytology or follow up of HPV DNA positive and cytology negative. These epidemiological data will be important to determine the future impact of vaccination on HPV infected women in our region.

Prevalence of Aflatoxin Induced p53 Mutation at Codon 249 (R249s) in Hepatocellular Carcinoma Patients with and without Hepatitis B Surface Antigen (HBsAg)

  • Chittmittrapap, Salyavit;Chieochansin, Thaweesak;Chaiteerakij, Roongruedee;Treeprasertsuk, Sombat;Klaikaew, Naruemon;Tangkijvanich, Pisit;Komolmit, Piyawat;Poovorawan, Yong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제14권12호
    • /
    • pp.7675-7679
    • /
    • 2013
  • Background: A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocellular carcinoma (HCC) patients with or without positive HBsAg. Materials and Methods: Paraffin embedded liver tissues were obtained from 124 HCC patients who underwent liver resection and liver biopsy in King Chulalongkorn Memorial Hospital. Restriction fragment length polymorphism (RFLP) was utilized to detect the R249S mutation. Positive results were confirmed by direct sequencing. Results: Sixty four (52%) patients were positive for HBsAg and 18 (15%) were anti-HCV positive. 12 specimens tested positive by RFLP. Ten HCC patients (8.1%) were confirmed to be R249S positive by Sanger sequencing (AGG to AGT). Out of these 10, six were HBsAg positive, and out of the remaining 4, two were anti-HCV positive. The R249S prevalence among HCC patients with positive HBsAg was 9.4% compared to 6.7% for HBsAg negative samples. Patients with the R249S mutation were younger ($55{\pm}10$ vs $60{\pm}13$ year-old) and tended to have a more advanced Edmonson-Steiner grade of HCC, although differences did not reach statistical significance. Conclusions: Our study shows moderate prevalence of aflatoxin B1-related p53 mutation (R249S) in HCC with or without HBsAg. HBsAg positive status was not associated with R249S prevalence.

Sensitive High-Resolution Melting Analysis for Screening of KRAS and BRAF Mutations in Iranian Human Metastatic Colorectal Cancers

  • Niya, Mohammad Hadi Karbalaie;Basi, Ali;Koochak, Aghigh;Tameshkel, Fahimeh Safarnezhad;Rakhshani, Nasser;Zamani, Farhad;Imanzade, Farid;Rezvani, Hamid;Adib sereshki, Mohammad Mahdi;Sohrabi, Masoud Reza
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권12호
    • /
    • pp.5147-5152
    • /
    • 2016
  • Background: Investigations of methods for detection of mutations have uncovered major weaknesses of direct sequencing and pyrosequencing, with their high costs and low sensitivity in screening for both known and unknown mutations. High resolution melting (HRM) analysis is an alternative tool for the rapid detection of mutations. Here we describe the accuracy of HRM in screening for KRAS and BRAF mutations in metastatic colorectal cancer (mCRCs) samples. Materials and Methods: A total of 1000 mCRC patients in Mehr Hospital, Tehran, Iran, from Feb 2008 to May 2012 were examined for KRAS mutations and 242 of them were selected for further assessment of BRAF mutations by HRM analysis. In order to calculate the sensitivity and specificity, HRM results were checked by pyrosequencing as the golden standard and Dxs Therascreen as a further method. Results: In the total of 1,000 participants, there were 664 (66.4%) with wild type and 336 (33.6%) with mutant codons 12 and/or 13 of the KRAS gene. Among 242 samples randomly checked for the BRAF gene, all were wild type by HRM. Pyrosequencing and Dxs Therascreen results were in line with those of the HRM. In this regard, the sensitivity and specificity of HRM were evaluated as 100%. Conclusion: The findings suggest that the HRM, in comparison with DNA sequencing, is a more appropriate method for precise scanning of KRAS and BRAF mutations. It is also possible to state that HRM may be an attractive technique for the detection of known or unknown somatic mutations in other genes.

인체 노로바이러스의 한국분리주 Hu/NLV/Gunpo/2006/KO의 분자생물학적 특성 (Molecular Characterization of a Korean Isolate of Human Norovirus, the Hu/NLV/Gunpo/2006/KO Strain)

  • 정아용;윤상임;지영미;강윤성;이영민
    • 미생물학회지
    • /
    • 제45권2호
    • /
    • pp.105-111
    • /
    • 2009
  • 노로바이러스는 급성 위장염을 일으키는 Caliciviridae 과(family)에 속하는 바이러스로 유전자형이 매우 다양하다. 본 연구에서는 노로바이러스 국내분리주의 게놈 RNA로부터 3개의 open reading frame (ORF) 모두의 염기서열을 분석하고, 유전학적 계통분석을 통하여 분자생물학적 특성을 분석하였다. 본 연구에 사용된 노로바이러스(Hu/NLV/Gunpo/2006/KO)는 바이러스성 식중독, 장염 증세를 보이는 2세 여아 가검물로부터 분리되었다. 역전사반응과 PCR 증폭을 통해서 바이러스의 게놈 RNA를 3개의 중첩되는 cDNA 단편으로 합성하였으며, 합성된 cDNA를 염기서열 분석에 직접 사용하였다. 시퀀싱 결과 Hu/NLV/Gunpo/2006/KO는 3개의 ORF (ORF1, 5,100 bp; ORF2, 1,647 bp; ORF3, 765 bp)로 구성되어 있음을 알 수 있었다. 35개의 노로바이러스 국외 분리주와 비교한 결과, ORF1은 ORF2 또는 ORF3에 비해서 상대적으로 염기의 변이율이 낮았으며, 특히 ORF2와 ORF3의 C-말단 부위에서 높은 변이율을 관찰하였다. 유전학적 계통도를 분석한 결과, Hu/NLV/Gunpo/2006/KO는 genogroup II 에 속하며, Saitama U1, Gifu'96, Mc37, Vietnam 026과 같은 클러스터를 형성하는 것을 알 수 있었다. 본 연구를 통하여 노로바이러스 Hu/NLV/Gunpo/2006/KO의 3개의 ORF 염기서열을 모두 밝힘으로써, 앞으로 노로바이러스의 검출법 개발과 유전학적 상관관계뿐 아니라, 유전자의 기능 분석과 관련된 기초연구에 중요한 기초자료를 제공할 수 있을 것으로 기대한다.