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What are the chemicals that cause damage to DNA known as?
Carcinogens are categorised as being chemical or physical agents [3], causing DNA damage attributable to their physico-chemical properties, such as DNA molecule distortion or DNA cross-linking [3–6].
What are some physical and chemical agents that cause mutations?
The chemical or physical agents that cause mutations are called mutagens. Examples of physical mutagens are ultraviolet (UV) and gamma radiation. Radiation exerts its mutagenic effect either directly or by creating free radicals that in turn have mutagenic effects.
What is DNA damage?
DNA damage is a change in the basic structure of DNA that is not itself replicated when the DNA is replicated. A DNA damage can be a chemical addition or disruption to a base of DNA (creating an abnormal nucleotide or nucleotide fragment) or a break in one or both chains of the DNA strands.
What causes DNA damage in sperm?
Ramsay added that the majority of DNA damage in sperm is caused when it’s in transit from testicle to ejaculation. This damage is spurred by oxidative stress, which can cause DNA single-strand breaks. Men who lead unhealthy lifestyle habits might want to listen up.
What is physical and chemical mutation?
Most chemical mutagens are alkylating agents and azides. Physical mutagens include electromagnetic radiation, such as gamma rays, X rays, and UV light, and particle radiation, such as fast and thermal neutrons, beta and alpha particles.
How do chemical mutagens affect DNA?
Chemical Mutagens Some mutagens strip DNA nucleotides (bases) of essential modifications—for example, they deaminate the bases—such that these bases resemble different nucleotides and confuse the DNA replication machinery. Subsequent rounds of DNA replication then permanently incorporate such changes.
How is damaged DNA repaired?
Most damage to DNA is repaired by removal of the damaged bases followed by resynthesis of the excised region. Some lesions in DNA, however, can be repaired by direct reversal of the damage, which may be a more efficient way of dealing with specific types of DNA damage that occur frequently.
What does damaged DNA mean?
When does sperm DNA damage occur?
Sperm DNA damage may favour chromosomal aberrations after first metaphase following fertilization as repositioning of paternal centromeres can interfere with normal cell division and development of embryo (22).
How do physical mutagens cause mutations?
Physical mutagens most often result in chromosome changes and larger DNA deletions while mutagenic chemicals typically cause point mutations. The degree of mutation also depends on the tissue and the time and dosage of exposure. DNA mutations are generally of the most interest to breeders.