A series of hamster crosses are performed to get an insight into the mode of inheritance of three coat colors: plain brown, plain beige, and patchy brown. Note that not all the parents were pure-breeding. Propose a mode of inheritance for coat color in hamsters, using symbols of your own choosing to identify genes and alleles. 

Cross	Parents phenotypes	F1 phenotypes
1.	Plain brown xx plain brown	14 plain brown
2.	Plain beige xx plain beige	12 plain beige
3.	Patchy brown xx patchy brown	6 patchy brown, 3 plain brown
4.	Plain brown xx plain beige	13 plain brown
5.	Patchy brown xx plain brown	6 plain brown, 7 patchy brown
6.	Plain beige xx patchy brown	7 plain brown, 3 patchy brown, 3 plain beige
7.	Plain beige xx plain beige	9 plain beige
8.	Plain brown xx plain brown	10 plain brown, 3 plain beige