"Because genes give rise to proteins that serve as cellular building blocks, signals and regulators of other genes, a mutation that disables one gene, or causes it to be overactive can have multiple deranging effects on the cell."
"Because genes give rise to proteins that serve as cellular building blocks, signals and regulators of other genes, a mutation that disables one gene, or causes it to be overactive can have multiple deranging effects on the cell."
"Changes in the structure or activity of genes underlie the malignant behavior of cancer cells."
"…Cancer is caused primarily by mutations in specific genes. The damage can be incurred through exposure to toxins or radiation, by faultty DNA repari processes or by errors that occur when DNA is copied prior to celldivision.In relatively rare cases, a cancer predisposing mutation is carried within a gene variant inherited from one's ancestors."
Whatever their origin , these mutations disrupt biological pathways in ways that result in uncontrolled cell replication, or growth...."
This approach has identified 350 cancer related genes and yielded many significant insights into this diabolical disease....But no one imagines that it is a complete list."
p. 52.
"The Human Genome Project laid a solid foundation for the TCGA [base-pair sequence code] by creating a standardized reference sequence of the three billion DNA base pairs of the normal human tissues." |
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"At the start of that project in 1990, for example, the cost of DNA sequencing was more than $10 per 'finished' nucleotide base. Today the cost is less than a penny per base and is expected to drop still further with the emergence of innovative sequencing methods." "Piles of data are, of course, not worth much without evidence that comprehensive knowledge of cancer's molecular origins can actually make a difference in the care of people." |
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molecules in base pairs |
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"But the group hit pay dirt a year later when they found that a gene called B-RAF was mutated in about 70 percent of the malignant melanoma cases they examined....a protein called MEK that is overp[roduced as a result of B-RAF mutations."
p. 53
Gordon Edlin, authority on human genetics writes, “Since the development of the Ames test and other biological tests to measuring the mutagenic potency of chemicals, it has become increasingly evident that we live in an environment full of mutagens.”
genetic factors in cancer
transcription (RNA from DNA)
duplication (DNA replicates)
in enzyme manufacture (shut down cell division, repair DNA sequences, triggers)
oncogenes -- cancer causing viruses, P-53 gene, src or “sark” gene when expressed
retroviruses (RNA takes over nuclear DNA)
Genes allow us, and all organisms, to adapt to a range of conditions to which we may readily respond. They create an opportunity, but do not–except in rare cases compel us, or doom us to some awful end purpose.
Scientific American, March 2007.
Genetics Index | What makes genetics significant? | History of Genetics | DNA discovery | RNA | Resistance| | Visual images
