What is the DNA repair hypothesis?
Abstract. The DNA repair hypothesis for the maintenance of sex states that recombination is necessary for the repair of double-strand DNA damage. In a closed (mitotic) genetic system crossing-over generates homozygosity. This reduces fitness if deleterious recessive alleles become expressed.
What are DNA damage response genes?
Several genes that participate in the DNA damage response, such as RAD9, PARP1, BRCA1, ATM and TP53 have been associated with metastasis by a number of in vitro biochemical and cellular assays, by examining human tumor specimens by immunohistochemistry or by DNA genome-wide gene expression profiling.
How does DNA damage cause cancer?
Genes that repair other damaged genes (DNA repair genes) But if the DNA damage occurs to a gene that makes a DNA repair protein, a cell has less ability to repair itself. So errors will build up in other genes over time and allow a cancer to form.
What is the DNA damage?
DNA damage is defined as an alteration in DNA structure that is capable of causing cellular injury and reduces viability or reproductive fitness of the organism (Kaufmann and Paules, 1996).
How does DNA damage impact health and life?
DNA damage contributes to aging via cell autonomous events such as causing apoptosis, which depletes functional cells such as neurons, and via cell non-autonomous mechanisms such as triggering senescence, which can negatively impact the function of neighboring, undamaged cells through their SASP.
What does DNA damage mean?
Which of the following can damage DNA?
DNA bases can be damaged by: (1) oxidative processes, (2) alkylation of bases, (3) base loss caused by the hydrolysis of bases, (4) bulky adduct formation, (5) DNA crosslinking, and (6) DNA strand breaks, including single and double stranded breaks. An overview of these types of damage are described below.
What are the three types of DNA damage?
What is a DNA damage response mechanism?
In response to chemotherapy drugs that either directly or indirectly damage DNA, DNA damage response (DDR) mechanisms can reverse the drug-induced damage. For example, platinum-containing chemotherapy drugs such as Cisplatin cause harmful DNA crosslinks, which can lead to apoptosis.
What is the role of DNA repair in drug resistance?
The repair of damaged DNA has a clear role in anticancer drug resistance. In response to chemotherapy drugs that either directly or indirectly damage DNA, DNA damage response (DDR) mechanisms can reverse the drug-induced damage.
How is DNA damaged by DNA replication bypassed?
DNA damage bypass can occur by recombination mechanisms or through a novel mechanism called translesion synthesis. Translesion synthesis employs an alternate DNA polymerase that can substitute for a DNA polymerase that has stalled at the replication fork due to DNA damage.
What is the process of DNA damage recognition and repair?
The processes of DNA damage recognition and repair are the focus of later sections within this chapter. There are a variety of types of mutations. Two major categories of mutations are germline mutations and somatic mutations. Germline mutations occur in gametes, the sex cells, such as eggs and sperm.