Good question-!!!!!!
Yep, and there is no scientifically reasonable answer besides strong speculations from other points of view such as spiritual. (biblical texts & upon that). Mutation does not cut it at all.
I am Rh-negative and have read most of it.
As to the guy above me who said, Rh-negative began from a child, it is scientifically impossible for both parents NOT having an Rh-negative allele to even begin by just losing the Rhesus alleles. In other words, it is impossible to suggest for a dominant gene which is already present by suggesting them that they become non-existent in their sperm-DNA's or ovum-DNA's and a whole immune system with antibodies against a specific protein/antigen such as Rhesus in this case just exist. Ask any geneticist whether an AB-blood person's child would ever become O-blood type.
A "copying error" a.k.a mutation on a very small scale on bloods causes the blood to die off. Ressessive genes are ressessive genes and are not a product of "copying errors", for their product is absolutely normal and very characteristic to itself.
I'm pretty sure, you already know how recessive genes go
"non-existent".
From my Christian point of view, it is ABSOLUTELY bunk that we evolved from any animals and obviously the product of Adam and Eve and created by God. However, since it cannot be logical or normal that an Rh-negative mother reject and kills her own offspring (of Rh-positive), there has to be another origin especially for the Rh-negative blood.
I speculate it on Genesis 6,4 and other sacred texts or apocryphas talking about the mixing of Watcher angels who were then given their "mortal tasks", to having failed their duties by mixing with human women and producing children who were known as nephilims or giants. Book of Enoch and several others also talk about that in detail about those angels. Enoch who witnessesd those watcher angels who were then imprisoned (although the Nephilims were judged differently and still were on earth) was taken up to heaven and never faced death. (also backed up in the New Testament). The speculation here is that the "nephilim blood" that links to the Watcher-angels were Rh-negative and the alleles were in Enoch's bloodline, a good reasoning as well as to why he was able to witness the Watcher angels in prison and also judging the fact that the New Testament says, we will be judging angels according to Peter. (who else are we judging since the hell's angels are already judged & heaven's angels needs no human judgements). The Rh-- alleles were supposedly passed on to Noah while the great flood destroyed the world besides the 8 of them.
The Bible also says that there were "giants" after the flood. Yep, the very reason alleles can team up and show off its recessive genes characteristics shows, Noah's alleles can later pair up and bring 'em up again. Yeah....there are also those Bigfoot and etc talks out there. Also read that Noah was fair and blonde, those also being ressessive traits of its own kind (not mutation).
Guess, you've researched and read'em all on the net as you said "you're tired of googling and....conspiracy theories" like nutty David Icke..hee-hee-! and whoever else.
There is no other way to justify, an Rh-negative mother can have antibodies against her own baby.
Book of Enoch was however not taken into account in the Bible although it is used by some early orthodox churches.
I can understand why the ancient issue needs to be buried since it wasn't from a legitimacy just like anyone would an "unwed child" today, which is good to not be in the Bible although Genesis 6,4 kinda spilled it out and made it. Jude of Old Testament mentions the Book of Enoch and she also talked a little about the angels. Was she Rh-negative? Was Elijah who were taken to heaven and did not face death Rh-negative? Only God knows.
I've also read stuff like "blood of the gods", aristocrat-blood, blue blood, noble blood etc although it sounds more like stuffs people have exploited with in the past in European history although it's kinda b/s because we're all somewhat equal. Guess you know-it-all.
[[[ You said: how is it proven that PPL with RH negative are not from mokies or apes? ]]]
Duplicating Rh-negative blood have been unsuccessful although Rh-positive blood has been done with. Rhesus protein is present on monkey's blood but this DOES NOT suggest that humans are from apes just because they have the Rhesus protein in them. I wouldn't say, I'm a fish just because I swim.
I'd wrap up for now. You sound like you're one of us or you wouldn't be so into researching this up. What's up and take care-!!!
So,
[[[ You said: "RH Negative blood. where did it come from?" ]]]
Watcher-angels.......LOL