Genome Entries 2

Chapter 3: Fate

Ridley uses the example of the Wolf-Hirschhorn gene, where individuals with the gene are healthy, those without the gene have Wolf-Hirschhorn syndrome, and those with a mutated version have Huntington’s chorea. In 1970, a woman named Nancy Wexler and her father knowing that she may carry the mutation for Huntington’s chorea, decided to search for the gene. The gene was finally found in 1993 and it solely a repetition of the codon CAG. Excess CAG repeats have been found to induce at least five other neurological disorders and at least twelve known human diseases. The number of repetitions can increase over time, except in the cerebellum, but especially in sperm production. Ridley then goes on to discuss how people handle the fate of testing positive for a genetic test for Huntington’s, and how it is not always wise to diagnose a disease that cannot be cured before its onset.

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