Board Thread:General Discussion/@comment-27104382-20151020184914/@comment-27094742-20151020201830

During the flashback image of turtles' origin Splinter didn't touch them. And given that Leo and Mikey have blue eyes and Raph has green eyes, its highly unlikely they would get blue or green eyes from Splinter who is full-blood Japanese.

Also, there is an interesting fact, at present Japanese law allows for adopted siblings to marry which has feudal-era origins.