Genetics at this level can be mind melting. At least to me. I have been studying and studying and all I know for sure at this point is how little I actually know. I have serious doubts however that the problem in ball pythons is melanin related. There is just too much evidence to the contrary. If the neurological issues are genetically linked to anything visual my bet would be severe pattern reduction. It seems to me to be the only common thread among the morphs that display the issue.