The original breeding that produced the first Mirage animals was a Pastel Ivory (produced by me) bred to a Pastel female (also produced by me), and it yielded 2.2 Super Pastel YB Mirage animals. One of those males is what Brandt bought. At that time, I didn't know how those animals would pass the gene, and therefore didn't want to name it yet. There were three criteria that I wanted to meet prior to naming the mutation.
#1, I wanted to ensure that a Mirage animal produced by me could reproduce the gene. Brandt was the first one to have an opportunity to do this, as he had a male, and I had kept a female from the first breeding. I can say that I have made Mirage animals three years in a row, by repeating the breeding that made them the first year in 2011.
#2, I wanted to ensure that the gene wasn't "linked" to YB. Brandt proved this by producing a Super Pastel Mirage that lacked the YB gene (this snake is pictured above).
#3, I wanted to make sure that the female Pastel I have been using isn't the animal passing the gene. Brandt again proved this, since he doesn't have my Pastel.
Brandt was able to help me determine that all of my criteria had been met, and therefore I wanted to name the mutation so that everyone could have something to call it. There is obviously more work to be done, and due to the animals I have, It has been hard for me to get the gene isolated from YB and Pastel, but it is a work in progrss. I can say that I have produced two Yellow Bellys and they are very extreme, and I believe they may be Mirage gene without the Pastel gene included. I will attempt to get some pics of those animals soon.