DNA repair

Deoxyribonucleic acid (DNA) is the hereditary material. It is a polynucleotide and is a double helix composed of two strand that run in opposite direction1. Each strand of DNA consist of a sugar molecule (deoxyribose), nitrogen base (adenine-A, guanine-G, thymine-T and cytosine-S) and a phosphate group. Adenine and guanine are double-ringed molecules known as purines while thymine and cytosine are single-ringed molecules known as pyrimidines1. Within the DNA molecule, the sugar molecules are…

The cell's native DNA repair machinery generally mends the cut — but often makes mistakes. Ledford, along with other scientists, agree that genetic editing has many risks, predominantly concerning the success rate of the procedure. In a study done by researchers at Sun Yat-sen…

tumor suppressor genes is to inhibit cell division and limit the growth of tumors. A type of tumor suppressor gene, known as the p53 gene, is known for its role in repairing damaged DNA. It will often activate other genes that help to slow down the cell cycle and buy some time to repair damaged DNA. If the damage caused to DNA is deemed irreparable, the p53 gene can activate genes responsible for apoptosis, which is programmed cell suicide. If tumor suppressor genes like the p53 gene are unable…

Skin cancer, the most common form of cancer in the United States, is defined as the uncontrolled growth of abnormal skin cells following unrepairable DNA damage to the skin. This DNA damage leads to cellular mutation and causes skin cells to multiply quickly, thus forming tumors and abnormal growths. There are several causes of skin cancer, including sunburn and ultraviolet light exposure throughout life with environmental and hereditary elements. Ultraviolet light, a type of electromagnetic…

Mutations are random permanent changes in the genome of an organism that may or may not result in phenotypical variation. Mutations can be stimulated by external events such as exposure to ionizing radiation as well as internal events such as errors in DNA replication like double strand breaks. In lab, we focused on mutations that exhibit phenotypic advantage or disadvantage to an organism in their respective habitats. The necessity of higher or lower mutation rates will vary based on whether…

is approximately one base pair change in one billion base pair per replication cycle. DNA error- checking and error- repair are two proccesses that occur and usually they prevent and repair mutations. For an organism to evolve from another, a huge rate of mutation must take place, a great amount of genetic information would be added, and the proofreading of DNA polymerase, an enzyme that is essential for DNA replication, would not be effective. There is no observed case that shows that this…

A, B and Z DNA Structure These three types of DNA all possess the similar property of a double helical structure formed from a sugar-phosphate backbone and containing the 4 bases, adenine, thymine, guanine and cytosine, complementarily paired with hydrogen bonding. A and G are purines and have a double ring whereas T and C are pyrimidines and have only a single ring. Within the helix a pyrimidine is always paired with a purine such that G is always paired with C and T with A. The difference…

makeup due to the uptake of exogenous DNA (Lorenz and Wackernagel, 1994). This process can happen in two different ways, either naturally or artificially. Natural Natural transformation is the bacteria’s ability to acquire naked DNA that is free roaming in the environment by being in a state that is achieved naturally termed competency (Transformation – Natural Transformation, n.d.). Competency of bacterial cells is their ability to pick up exogenous DNA and plays a very important…

Genomic engineering is the process of modifying specific sites in DNA sequences of cells or organisms. The ability to achieve effective and precise editing of the genome has been achieved and advanced through the development of sequence-specific nucleases1. Zinc-finger nucleases and transcription activator-like effector nucleases (TALENs) are programmable DNA binding nucleases previously used to achieve this targeted editing of DNA. However these tools have been found to be both time consuming…

different genes in multiple myeloma. This was tested using the cross chromatin immunoprecipitation technique, coupled with the use of genomic sequencing. This technique offers to discern the sites at which the HIF1 and HIF2 proteins are binding to the DNA, and allow to infer the likelihood that these two proteins are regulating different genes in…