I was told today that my blood group is 0-, but my parents have A+ and B- Is this possible?

Answer

Best,

That can be perfectly correct. Your blood group (AB) and your rhesus factor (+ -) are determined by two genes. If you have neither the gene for A nor the gene for B, then you have blood type O.

So there are some conditions

your parent who has A+ has genes AO and Rh + –

your parent who has B- has genes BO and Rh – –

As a child of those parents you can of course also be B-, B+, O+, AB +, AB-, A+ or A-. In fact everything.

Kind regards