CHAPTER 10 Summary

• Cancer is uncontrolled cell division caused by mutations in DNA.
• Mutations occur spontaneously during DNA replication. They can also be caused by environmental triggers such as tobacco or UV radiation and by chemicals naturally produced by the body.
• Mutations in certain genes can lead to cancer if they damage the normal function of the proteins those genes code for.
• Mutations in two types of gene, proto-oncogenes and tumor suppressors, cause most cancers.
• Multiple mutations must occur in the same cell for it to become cancerous.
• Mutations that occur in somatic (body) cells, for example skin or breast cells, are not inherited by offspring. Mutations that occur in germ (sperm or egg) cells are inherited by offspring.
• People with “hereditary” cancer inherit predispositions to the disease in the form of specific genetic mutations. These mutations are present in all body cells and can serve as the first mutation that may lead to cancer.
• Women with BRCA mutations have a much higher risk of developing cancer, and at an earlier age, than women without these mutations.
• Mutations introduce new alleles into the population. These alleles may code for proteins that have advantageous, neutral, or harmful effects on an individual.
• Certain alleles are more common in ethnic groups that have been reproductively isolated for long periods of time.

• MORE TO EXPLORE

  • National Cancer Institute FactSheet: BRCA1 and BRCA2 http://www.cancer.gov/cancertopics/factsheet/Risk/BRCA
  • American Cancer Society: Heredity and Cancer http://www.cancer.org/cancer/cancercauses/geneticsandcancer/heredity-and-cancer
  • Susan G. Komen for the Cure http://ww5.komen.org/
  • Genetic Disease Foundation http://www.geneticdiseasefoundation.org/
  • Center for Jewish Genetics http://www.jewishgenetics.org/