Everyone is having incest

Woah, I am the product of THAT many people? 0_o cool

and i still get the ugly jeans :(

One of my 13times great grandfathers was a student of Bach.
But I guess everyone's was ...

Define 'related'. Of course we're related to other humans, we share the same fucking DNA. We're even related to chimps, we share about 99% DNA with them, too.
Incest is not so much about DNA as it is about being raised as siblings, etc. The thing that is about DNA, however, is consaguinity.

Not really. You're probably related through many marriages to some people and not related at all to others.

So can I or can I not date my step cousin though?

Adam and Eve