What happens if a DNA strand breaks?

What happens if a DNA strand breaks?

Repairing Double-Strand DNA Breaks. Double-strand breaks in DNA can be lethal to a cell. DSBs are particularly troublesome because they can lead to cell death if not repaired. And, if not repaired correctly, DSBs can cause deletions, translocations, and fusions in the DNA.

How is DNA break measured?

Breaks in DNA reduce the molecular weight of a single DNA strand, and this may be caused by physical, chemical or enzymatic reagents (6). DNA breaks and lesions may be detected by PCR or using agarose gel electrophoresis (7). PCR is one of the most frequently used techniques for detecting DNA damage (7).

What causes DNA strands to break?

Abstract. The DNA double-strand break (DSB) is the principle cytotoxic lesion for ionizing radiation and radio-mimetic chemicals but can also be caused by mechanical stress on chromosomes or when a replicative DNA polymerase encounters a DNA single-strand break or other type of DNA lesion.

What protein breaks the DNA strand?

helicase
Then, a protein known as helicase attaches to and breaks apart the hydrogen bonds between the bases on the DNA strands, thereby pulling apart the two strands. As the helicase moves along the DNA molecule, it continues breaking these hydrogen bonds and separating the two polynucleotide chains (Figure 1).

How do you treat damaged DNA?

At least five major DNA repair pathways—base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination (HR) and non-homologous end joining (NHEJ)—are active throughout different stages of the cell cycle, allowing the cells to repair the DNA damage.

What DNA repair means?

DNA repair, any of several mechanisms by which a cell maintains the integrity of its genetic code. DNA repair ensures the survival of a species by enabling parental DNA to be inherited as faithfully as possible by offspring. It also preserves the health of an individual.

What are possible negative consequences of breaking apart human DNA?

DNA may be modified in a variety of ways, which can ultimately lead to mutations and genomic instability. This could result in the development of a variety of cancers including colon, breast, and prostate.

What happens if DNA is damaged?

DNA damage can affect normal cell replicative function and impact rates of apoptosis (programmed cell death, often referred to as ‘cellular senescence’). Alternatively, damage to genetic material can result in impaired cellular function, cell loss, or the transformation of healthy cells to cancers.