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Principles and Techniques for Deoxyribonucleic Acid (DNA) Manipulation
Published in Hajiya Mairo Inuwa, Ifeoma Maureen Ezeonu, Charles Oluwaseun Adetunji, Emmanuel Olufemi Ekundayo, Abubakar Gidado, Abdulrazak B. Ibrahim, Benjamin Ewa Ubi, Medical Biotechnology, Biopharmaceutics, Forensic Science and Bioinformatics, 2022
Nwadiuto (Diuto) Esiobu, Ifeoma M. Ezeonu, Francisca Nwaokorie
The nitrogenous base in a nucleotide can be either a purine (double-ringed) or a pyrimidine (single-ringed). Four types of nitrogenous bases are found in DNA: adenine (A), guanine (G), cytosine (C) and thymine (T). Structures of these bases are shown in Figure 1.1c. RNA, on the other hand, contains the bases A, G, C, but T is replaced by another pyrimidine, uracil (U). The structure of uracil is shown in Figure 1.1d.
Gene Therapy for Cancer Treatment
Published in Yashwant V. Pathak, Gene Delivery Systems, 2022
Manish P. Patel, Mansi S. Shah, Mansi N. Athalye, Jayvadan K. Patel
The new human genome era is creating an increase in possibilites for genomics-based medicine, which is known as “personalized medicine.” In medicine, gene therapy is defined as a therapeutic strategy that transfers DNA to a patient’s cells to correct a defective/imperfect gene or a gene product in order to treat diseases which are not curable with conventional drugs [Shahryari et al. 2019]. Gene therapies can work by several mechanisms, like replacing a disease-causing gene with a healthy copy of the gene, inactivating a disease-causing gene that is not functioning properly or introducing a new or modified gene into the body to help in treatment of a disease. Studies have shown that gene therapy techniques have broad potential applications in cancer, and almost over 65% of all ongoing clinical gene trials are related to cancerous diseases [DAS et al. 2015].
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Published in Valerio Voliani, Nanomaterials and Neoplasms, 2021
Eun-Kyung Lim, Taekhoon Kim, Soonmyung Paik, Seungjoo Haam, Yong-Min Huh, Kwangyeol Lee
Gene therapy is the use of genes as medicine that involves the transfer of a therapeutic or working gene (DNA and RNA) copy into specific cells of a patient in order to repair gene defects due to mutations [403–409, 413, 420–426]. This technique has been studied in clinical settings for a variety of cancer types and other disease involving gene defects. Cancer cells possess upregulated or inappropriately expressed genes, which leads to uncontrolled cell growth. Identification of target genes could lead to development of tailored anticancer agents with which the toxic side effect of cancer chemotherapies could be overcome. For example, RNAi-based gene therapies, i.e., sequence-specific post-transcriptional silencing of gene expression mediated by small double-stranded (dsRNA), have the potential to treat a variety of human genomic disorder, especially in combination with conventional therapies such as chemotherapy [419, 424]. Whereas knockdown of a target mRNA is not feasible with sense and antisense RNAs, dsRNA can lead to an effective and a specific mRNA knockdown. After dsRNA is introduced into cells it is cleaved by the enzyme dicer, a member of the RNaseIII family of dsRNA-specific ribonucleases [407, 409, 421, 424]. This enzymatic cleavage degrades the RNA to 19–23 bp duplexes, each with a 2-bp 3′ overhang [703, 408, 422].
Image Encryption using DNA Coding and Hyperchaotic System
Published in IETE Technical Review, 2020
M. Kar, A. Kumar, D. Nandi, M. K. Mandal
The Deoxyribonucleic acid (DNA) is a molecule that contains the genetic information of all the living organisms. The development and function of the organisms depend on the structure of its DNA molecule. A DNA structure consists of four nucleic acid bases adenine (A), cytosine (C), guanine (G) and thymine (T). According to Watson-Crick base pairing rules [11,19], A and T are complementary and G and C are complementary. In the binary representation 0 and 1 are complementary, similarly, we can say 00 and 11 are complementary and also 01 and 10 are complementary. By considering the complementary rule, we may use A, C, G and T to denote 00, 01, 10 and 11, respectively. This is an example of one possible representation and other representations are given in Table 1. An image pixel value (8-bits binary number) may be represented by four binary numbers each consisting of two bits. These numbers are mapped to their corresponding DNA sequence. Therefore, each pixel of the image is represented by four acid bases. The 8-bit pixel value can be encoded in 24 possible ways using 4 bases but Watson-Crick base pairing rules support only 8 representations as listed in Table 1. For example, if the decimal value of a pixel is 53, its 8-bit binary representation is 00110101, then it is encoded as a DNA sequence CGAA according to rule 5 in Table 1. Inversely, the pixel value can be decoded by DNA sequence, for example, DNA sequence TCTC is decoded as 10111011 by rule 7 and the corresponding decimal value is 187.
A Chaotic Approach to Recognize the Characteristics of Genetic Codes of Covid Patients
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2023
A cell is the basic scale of every living organism. By examining the gene expression, we can get information about some characteristics of the particular organism. In the examination of the gene expression process, the DNA sequence plays a vital role. DNA sequencing is the process of deciphering a strand of DNA nucleotide sequence (A, C, G, and T). The information needed by a cell to build protein and RNA molecules is included in the DNA base sequence. In short, it functions similarly to a switch that turns on or off protein synthesis. It also plays a key role in the determination of the molecular signature of diseases.
Gene doping: Present and future
Published in European Journal of Sport Science, 2020
Rebeca Araujo Cantelmo, Alessandra Pereira da Silva, Celso Teixeira Mendes-Junior, Daniel Junqueira Dorta
According to Haisma and de Hon (2006), gene therapy can be defined as “the transfer of genetic material to human cells for treatment or prevention of a disease or disorder. Genetic materials can be DNA, RNA or genetically altered cells” (Haisma & de Hon, 2006, p. 259). Despite the great development of the gene therapy area over the years, this therapy still poses numerous limitations and risks, such as the patient’s immune response and consequent treatment rejection (Artioli et al., 2007; Gaffney & Parisotto, 2007; Haisma & de Hon, 2006; Karthikeyan & Pradeep, 2006).