CAMPBELL HAMSTER GENETICS

First of all, please notice the following genetic codes for each hamster color:

WILD COLOR (Dominant):
Agouti - A

SINGLE GENE COLORS (Recessive):
Black - aa
Black Eyed Argente - bb
Albino - cc
Opal - dd
Argente - pp

TWO-GENE COLORS (Recessive):
Blue - aa dd (Black + Opal)
Dove - aa pp (Black + Argente)
Blue Fawn - dd pp (Opal + Argente)
Beige - bb pp (BEA + Argente)
Lilac Fawn - bb dd (BEA + Opal)
Chocolate - aa bb (Black + BEA)

THREE-GENE COLORS (Recessive):
Red Eye Lilac - aa dd pp (Black + Opal + Argente)
Black Eye Lilac - aa bb dd (Black + BEA + Opal)
Dark Beige - aa bb pp (Black + BEA + Argente)
Blue Beige - bb dd pp (BEA + Opal + Argente)

Disregarding the pattern genes for now, let us try to guess the genes of the parents using the litter produced.

For example, Hamster A is a blue female and Hamster B is a blue fawn male. Bred together, they produced 8 pups. 4 opals, 2 blues, and 2 blue fawns.

If Hamster A is a pure blue female (aa dd), and Hamster B is a pure blue fawn male (dd pp), they are supposed to produce 8 opals [dd], 2 of which will have unpaired black genes [a_] and two will have unpaired argente genes [p_]).

[Why? Because for every pair of genes the parents have, each offspring will inherit one. if a hamster has aa dd, he/she can only give one a, and one d. The other parent having dd pp can only give one d, and one p.]

However, in the scenario given, since they produced 2 blues and 2 blue fawns instead, the closest guess we can have of their parents' genes is the following:

Hamster A = aa dd p_
the color blue appears because the argente gene is unpaired.

Hamster B = dd pp a_
the color blue fawn appears because the black gene is unpaired.

PS: This is only an example.

-MasterHamster