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Chapter 18: Cures

The is about genetic manipulation, and the first example is in 1972 Paul Berg made the first man made recombinant DNA by using restriction enzymes and ligase. After that, there have been several experiments using recombinant DNA where a retrovirus would be stripped of its infectious genes and replaced with a desired gene and then injected into the body either directly or through cultured cell, trying to cure various diseases through gene therapy such as SCID, hemophilia, cystic fibrosis, and cancer. Genetic engineering has very unnecessarily polarized its proponents and radical environmentalists, stemming from the issue of agricultural genetic engineering. Ridley explains the possibilities of human cloning with genetic improvement through the use of embryonic stem cells and recombinant DNA.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 17: Death
A gene called TP53 is responsible for suppressing rogue cancer cells and is classified as a tumor suppressor gene. These genes are the opposite of oncogenes, which are genes that encourage cell growth. Ridley explains that the reason detecting cancer early is so important is that the more it progresses and the more the cells divide, the more mutations accumulate. Some cancer victims also carry mutations in mutator genes. Ridley explains that in various types of cancers TP53 is mutated very early, which is why chemotherapy and radiation therapy does not always work effectively in later stages of the disease.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 15: Sex

Prader-Willi syndrome and Angelman’s syndrome, both are caused by the lack of the same chunk of chromosome 15, and it has been shown that whether a child inherits one syndrome or the other depends on the parent from whom the mutation is inherited. This relates to sexual antagonism and the fact that the placenta is controlled by paternal genes. Genetic cloning seems to erase all genetic imprints so the organism still survives. Imprinting has an effect on the brain too, that the mother’s genes control the development of the cerebral cortex while the father’s control the development of the hypothalamus, so essentially we inherit our mother’s way of thinking and our father’s innate moods.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.

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Chapter 14: Immortality

James Watson discovered that polymerases do not start copying DNA at the tip of the chromosome, they start coding part way into the DNA. Telomerase is most likely responsible for increasing the continuous division of cells. Malignant cancer cells switch the gene on after it has been switched off by most cells in development. Ridley discusses why aging may be caused by evolution, and said that “Natural selection has designed all parts of our bodies to last just long enough to see our children into independence, no more.” So, cancer is most definitely linked to age.

Citation:

Ridley, Matt. Genome: The Autobiography of a Species in 23 Chapters. New York: HarperCollins, 1999. Print.