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Understanding Cancer Series

  • Posted: 12/29/2009

Slide 15


Genotypes, Phenotypes and Alleles

All genotypes are not created equal in their influence on phenotype. Genes come in many varieties called alleles, and some are more dominant than others. In a pair of alleles, the effect of a dominant allele prevails over the effect of a recessive allele. And the effects of a recessive allele become apparent only if the dominant allele becomes inactivated or lost.

Graphic shows how all genes are not equal in their ability to influence a cell. Varieties called dominant alleles prevail in creating effects over a counterpart recessive allele.