Users of only uchiha,senju, or uzumaki may only obtain this though blood lines or transplants.
Only Uchiha's may obtain though there blood lines
- Transplants are allowed for non-uchiha but needs deep background of how you obtained it.
Hyuuga's just like uchihad
- Transplants are allowed for non
Female Sharingan's & Rinnegan's
I know how girls feel to have a powerful character but theres a limit to where its to fiction and this by having the rinnegan....only known female to have rinnegan is Kaguya Otsutsuki because of the shinju fruit.