Deoxyribonucleic acid (DNA) is known as the “Thread of Life” and its own unique structure helps it maintain its virtue during its replication. DNA carries genetic information from one generation to another which is essential for the development, reproduction, and functioning for most living organisms.
Structure
DNA is a bipolymeric strand of nucleotides, whose structure was revealed by James D. Watson and Francis Crick in 1953, based on the x-ray diffraction patterns performed by Roaslind Franklin and Maurice Franklin. The DNA is a twisted ladder like structure, giving it its double helical structure, where each nucleotide is formed of a monosaccharide sugar (deoxyribose) and a phosphate group that act as a backbone of the structure. It also …show more content…
The DNA damage can happen due to mistake in mismatch repair, single or double strand breaking, addition, and conversion of cytosine to uracil due to presence of reactive oxygen species (Figure 3). Figure 3. A representation of the DNA damaging agents, the repair process, and the consequences of failure to repair. (Adapted from Hoejimakers, 2001).
There are several types of DNA repair depending on the damage. UV light damage is repaired via “nucleotide excision repair” (NER), which involves the work of about 30 genes, resulting in 18 proteins that would: a) detect the damage, b) excise the damaged section of DNA, c) resynthesizing the complementary DNA, and d) ligating the nick and returning the double strand formation (Clancy, 2008).
Another process is called the Base Excision Repair (BER), which repairs damage by free radicals by DNA glycosylase, which removes the damaged bases (Clancy, 2008).
Double stranded breaks (DSB) are repaired through nonhomologous end joining (NHEJ) or Homologous Recombination Repair …show more content…
For example, 5-10% of all breast cancers and 15% of ovarian cancers are caused by mutations in DNA repair genes BRCA1 and BRCA2. BRCA1 and BRCA2 are known as ‘tumor suppressor genes’ that are involved in the signaling and repair of DSBs in DNA during DNA replication. The genes have also been shown to play a role in chromosomal stability (Yoshida and Miki, 2004). To date, more than 1800 mutations in each of the BRCA have been identified. Inherited mutations in BRCA genes increases the susceptibility to breast cancer and/or ovarian cancer due to the accumulation of genetic alterations as a result of failure to repair DNA
Structure
DNA is a bipolymeric strand of nucleotides, whose structure was revealed by James D. Watson and Francis Crick in 1953, based on the x-ray diffraction patterns performed by Roaslind Franklin and Maurice Franklin. The DNA is a twisted ladder like structure, giving it its double helical structure, where each nucleotide is formed of a monosaccharide sugar (deoxyribose) and a phosphate group that act as a backbone of the structure. It also …show more content…
The DNA damage can happen due to mistake in mismatch repair, single or double strand breaking, addition, and conversion of cytosine to uracil due to presence of reactive oxygen species (Figure 3). Figure 3. A representation of the DNA damaging agents, the repair process, and the consequences of failure to repair. (Adapted from Hoejimakers, 2001).
There are several types of DNA repair depending on the damage. UV light damage is repaired via “nucleotide excision repair” (NER), which involves the work of about 30 genes, resulting in 18 proteins that would: a) detect the damage, b) excise the damaged section of DNA, c) resynthesizing the complementary DNA, and d) ligating the nick and returning the double strand formation (Clancy, 2008).
Another process is called the Base Excision Repair (BER), which repairs damage by free radicals by DNA glycosylase, which removes the damaged bases (Clancy, 2008).
Double stranded breaks (DSB) are repaired through nonhomologous end joining (NHEJ) or Homologous Recombination Repair …show more content…
For example, 5-10% of all breast cancers and 15% of ovarian cancers are caused by mutations in DNA repair genes BRCA1 and BRCA2. BRCA1 and BRCA2 are known as ‘tumor suppressor genes’ that are involved in the signaling and repair of DSBs in DNA during DNA replication. The genes have also been shown to play a role in chromosomal stability (Yoshida and Miki, 2004). To date, more than 1800 mutations in each of the BRCA have been identified. Inherited mutations in BRCA genes increases the susceptibility to breast cancer and/or ovarian cancer due to the accumulation of genetic alterations as a result of failure to repair DNA