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Understanding Cancer Series

  • Posted: 01/28/2005
  • Reviewed: 09/01/2006

Slide 14



Genes come in pairs, with one copy inherited from each parent.

Many genes come in a number of variant forms, known as alleles. A dominant allele prevails over a normal allele. A recessive allele prevails if its counterpart allele on the other chromosome becomes inactivated or lost.