Search results
Results from the WOW.Com Content Network
Similar to DNA crosslinking, DNA-protein crosslinks are lesions in cells that are frequently damaged by UV radiation. The UV's effect can lead to reactive interactions and cause DNA and the proteins that are in contact with it to crosslink. These crosslinks are very bulky and complex lesions.
The two subpathways differ in how they recognize DNA damage but they share the same process for lesion incision, repair, and ligation. The importance of NER is evidenced by the severe human diseases that result from in-born genetic mutations of NER proteins. Xeroderma pigmentosum and Cockayne's syndrome are two examples of NER associated diseases.
Deficient expression of DNA repair proteins due to an inherited mutation can cause increased risk of cancer. Individuals with an inherited impairment in any of 34 DNA repair genes (see article DNA repair-deficiency disorder ) have an increased risk of cancer, with some defects causing up to a 100% lifetime chance of cancer (e.g. p53 mutations ...
Radiation exposure through ionizing radiation (IR) affects a variety of processes inside of an exposed cell. IR can cause changes in gene expression, disruption of cell cycle arrest, and apoptotic cell death. The extent of how radiation effects cells depends on the type of cell and the dosage of the radiation.
Alternatively, if two similar viruses have infected the same host cell, homologous recombination can allow those two viruses to swap genes and thereby evolve more potent variations of themselves. [91] Homologous recombination is the proposed mechanism whereby the DNA virus human herpesvirus-6 integrates into human telomeres. [92]
The accumulation of certain mutations over generations of somatic cells is part of cause of malignant transformation, from normal cell to cancer cell. [ 112 ] Cells with heterozygous loss-of-function mutations (one good copy of gene and one mutated copy) may function normally with the unmutated copy until the good copy has been spontaneously ...
The ability for the wrong tautomer of one of the standard nucleic bases to mispair causes a mutation during the process of DNA replication which can be cytotoxic or mutagenic to the cell. These mispairings can result in transition, transversion, frameshift, deletion, and/or duplication mutations. [18]
[citation needed] Geneticists can also use this method to infer the presence of certain genes. Genes that typically stay together during recombination are said to be linked. One gene in a linked pair can sometimes be used as a marker to deduce the presence of the other gene. This is typically used to detect the presence of a disease-causing ...