Do you have Rh negative blood?
Don't be fooled by disinformation agents and their Facebook pages and websites making claims that Y DNA R1b is the Rh negative gene. There might be high percentages of type O blood in the Basque area, and this is because it is the place most of the Cro-Magons first created were based, when the Neandethals bred with the simian people they created. That area will then have mostly O positive, O negative, A positive and A negative blood types from the mixing. R1b is Cro-Magnon DNA, not Neanderthal, they are Hybrids, not pure. It would be silly to claim that Rh neg blood has its origin in R1b, especially as R1b came into the UK and Ireland much later than the I and J lines. R1b is the most common group of all in Europe, and yet Rh neg is very rare. I and J males carry the Rh neg genetics and mtDNA H and U groups. mtDNA haplogroup U is the most common in the Basque area, meaning the Cro-Magnon R1b males were breeding with pure blooded females. That is why so many of them have O negative blood, nothing to do with R1b.
Some people are determined to spread false information, they are either completely ignorant or just don't check their facts and just copy and paste other peoples false information.