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For example, certain intensities of exposure to radioactive elements can inflict damage to an organism's genome, heightening rates of mutation. In humans, the appearance of skin cancer during one's lifetime is induced by overexposure to UV radiation that causes mutations in the cellular and skin genome. [107]
Lewis Stadler, Muller's contemporary, also showed the effect of X-rays on mutations in barley in 1928, and of ultraviolet (UV) radiation on maize in 1936. [8] In 1940s, Charlotte Auerbach and J. M. Robson found that mustard gas can also cause mutations in fruit flies. [9]
One of the largest promoters of apoptosis is exposure to ultraviolet (UV) light. While UV light is essential to human life it can also cause harm by inducing cancer, immunosuppression, photoaging, inflammation, and cell death. [1] Of the various components of sunlight, ultraviolet radiation B (UVB) (290-320 nm) is considered to be the most harmful.
In such methods, cells or organisms are exposed to mutagens such as UV radiation or mutagenic chemicals, and mutants with desired characteristics are then selected. Hermann Muller discovered in 1927 that X-rays can cause genetic mutations in fruit flies, [6] and went on to use the mutants he created for his studies in genetics. [7]
“Skin cancer is caused by exposing the cells in the skin to UV radiation, and particularly UVB radiation,” researcher Dr. Rachel Neale told CNN Medical Correspondent Meg Tirrell recently in a ...
Ultraviolet radiation exposure is therefore the proposed underlying mutagenic mechanism of this signature. UV also illustrates a subtlety in interpreting a tumor signature as a mutagen signature: only three-quarters of mutations induced by UV in the laboratory are UV signature mutations because UV also triggers cellular oxidative processes. [2]
Damage caused by exogenous agents comes in many forms. Some examples are: UV-B light causes crosslinking between adjacent cytosine and thymine bases creating pyrimidine dimers. This is called direct DNA damage. UV-A light creates mostly free radicals. The damage caused by free radicals is called indirect DNA damage.
Xeroderma pigmentosum (XP) is a genetic disorder in which there is a decreased ability to repair DNA damage such as that caused by ultraviolet (UV) light. [1] Symptoms may include a severe sunburn after only a few minutes in the sun, freckling in sun-exposed areas, dry skin and changes in skin pigmentation. [1]