I love the look of grafted corals thats y ima go ahead and try this it would be incredible if it works out! Ive read plenty on gfp if ur referring to green fluorescent proteins and have heard of many cases where corals(especially sps) in close proximity to eachother the diff strains of zooxanthellae can "infect" as they refer to it on that article but its not very common and cant really be forcefully done or controlled, grafting on the other hand can be. Ive thought about this concept for awhile and has had me wondering if it would be possible to use a really tiny needle to try and extract zoox from one coral and inject in another, sounds cool but also crazy and highly unlikely tho lol idk??