Most ball python single-gene morphs came from wild-caught animals with a novel mutation. The vast majority of ball python morphs are also dominant/co-dominant. This means that an individual snake needs only *one* copy to display something other than the wild-type patterning. Thus a lesser/butter has a *single* lesser/butter gene and a *single* normal gene at that location, genetically. When they pass on their genetics to offspring, each parent provides half their genetic makeup towards the new individual. Thus, each lesser has only a 50% chance of passing on the lesser gene. So a lesser x lesser pairing will give you approximately 25% normal looking animals, because they didn't get a lesser gene from either parent, 50% lessers because they got a single gene from a single parent, and ~25% Super Lessers (blue-eyed leucistic), having received a lesser gene from both parents.Quote:
Originally Posted by JiBster816
Now, the lesser gene would have first popped up due to an error when the genome of one parent was being copied. That parent would have looked normal, but the offspring would have gotten a mutated copy, resulting in a non-normal snake.