I was reading the question and answers found here and I realized something. Distinction between half-bloods and pure-bloods were done using Third Reich rules for Jews. Well in order for magic to exist a "first" Wizard (or witch) should exist. The specific first was muggle born. Given that the first was alone his/her children would be half bloods. If he/she was not alone (let's say another one was created from another family) their children were both descendants of muggle borns.
So in theory all magicians in the magic world are descendants of muggle borns. Unless In the whole harry potter universe exists a "creation/evolution" theory in which the first wizard/witch descended from a different kind of species (or created by god alongside adam and eve even though I do not accept the creationists theory IRL, I would accept it in mythology).
Is there a canon answer to this? Are all Wizards descendants of Muggle borns?