Almost everybody has a different line on where they would consider Whiteness to end. For example, I've seen some people say Turks aren't White, or that Northern Africans (because of Roman occupation and colonization) are. I'm pretty sure Nazi Germany believed Slavs were not White. I'm interested to know where YOU draw the line, because there is rarely a consensus reached, and I rarely if ever see this asked.
Just please don't start a flamewar in the comments, I don't wanna come back to this post and see a bunch of arguing. Keep it respectable.
But it's a matter of biology and genetics, not opinion.