Egg Color Genetics for Dummies

[hollandhens24]

I have chickens because they are a functional animal, but have grown to love them just as little yard friends. That being said, I also enjoy that chickens and their eggs come in all shapes, sizes, and colors. I have been trying to get "fun" colored eggs like blues and greens since I first got chickens and had rotten luck with my first EE getting eaten by a neighbor's dog. I purchased two Whiting True Blues from McMurray last spring, a hen and a rooster, with the hope of creating my own little rainbow flock. My WTB hen lays white eggs...my last hope was seeing what color eggs the pullets hatched this spring lay late this summer/fall (hatched March 4, 2025) to indicate that at least my WTB rooster carries the blue egg gene. To my surprise, I had this tiny little egg in the coop. I am not sure which of the pullets (2 WTB or 1 WTB x Silkie) laid it, but was surprised when it was cream, not blue like I had anticipated out of these crosses. I suspect due to the incredibly small size it may be the WTB x silkie pullet.

I have very limited knowledge of chicken genetics, but I was under the impression that the blue gene is dominant; therefore the offspring of my Whiting True Blue rooster and any of my flock: whiting true blue, australorp, welsummer, silkie, would all lay a blue or olive green egg. Can someone please explain to me the basics of egg color genetics that I am clearly missing? Either my silkie chicken had a fluke EXTRA tiny egg today, or one of my pullets has begun laying and has confirmed that neither of my Whiting True Blues carry the blue egg gene. What in the world has a girl got to do to get a blue egg around here?!