LABRADOR RETRIEVERS AND EPISTATIC ALLELES

• A population might have more than two alleles for a given gene.
• In labrador retriever, coat color is determined by one gene with four different alleles. Five different colors result from the combinations of these alleles.
• Even if more than two alleles exist in a population, any given individual can have no more than two of them: one from the mother and one from the father.

  Labrador Retriever Genetics

  Black is dominant to chocolate B or b
  Yellow is recessive epistatic (when present, it blocks the expression of the black and chocolate alleles) E or e

Phenotype	Possible Genotypes
	BBEE BbEE BBEe BbEe
	bbEE bbEe
	BBee Bbee bbee

Task: Determine the number of chocolate labs produced from a black female and a yellow male (BbEe x bbee)

See if you can figure out how the multiple alleles act together to determine the coat color of a mouse. There are three varieties of coat color: black, brown, and white are controlled by four different alleles (similar to the labradors)