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Understanding Cancer Series

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

Slide 16


Altered Recessive Genes

In diseases associated with altered recessive genes, both parents--though disease free themselves--carry one normal allele and one altered allele.

Each child has one chance in four of inheriting two altered alleles and developing the disorder; one chance in four of inheriting two normal alleles; and two chances in four of inheriting one normal and one altered allele and being a carrier like both parents.

Altered Recessive Genes