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](https://webarchive.library.unt.edu/web/20090114182517im_/http://www.cancer.gov/images/Documents/2bb8687b-eb2b-4e62-ba30-a0572dee414e/cancer17.jpg)
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