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Drake's rule Let $L$ be the size of the genome. Let $\mu$ be the average per nucleotide mutation rate, then the genome-wide mutation rate $U$ is $U=L \mu$. There is a general relationship between the genome size of an organism and the nucleotide mutation rate that makes that the genome-wide mutation rate is often approximatively 1. There is of course ...


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How can a non-mutagenic agent be carcinogenic? An agent that causes overexpression of oncogenes or inhibition of tumor supressors, would be carcinogenic but not mutagenic. HPV, for instance, produces proteins that cause inactivation and degradation of tumor suppressors, p53 and pRb[1]. Regarding alcohol. As you guessed, alcohol is metabolized to form ...


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Alcohol itself is non-mutagenic because it does not directly alter DNA. (Additionally ethanol enhances carcinogenesis and is itself not a carcinogen - updated) There are similar non-mutagenic carcinogens such as estrogen - which is a carcinogen. Another important thing to realize is that a non-mutagenic carcinogen may not alter DNA, but instead alter ...


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NRAS is indeed a molecular switch, as part of the MAP-Kinase signaltransduction pathway it acts in controling the signal which goes downstream and finally will cause the expression of genes. In the case of NRAS this includes genes for proliferation, which is important for tumors. In principle, this looks like shown on this figure (from here): RAS (this is ...


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