I was sitting here wondering, how do you get a Thai flag betta??

Someone told me you have to have marble genes in the line....but what else? Is it one of those things where you get lucky and end up with one with just the right amount of red, white and blue?? Or can you successfully breed for it and end up with a good percentage like 25% thai flag??

I mean they are kind of a glorified multicolor where the colors end up seperated....so do you have to have butterfly genes too??

Thanks!