Why my parents’ blood group is B positive and mine is AB positive. How is this possible?

@Wateribbon umm, they are right .
There is literally a sale on Ancestry kits online right at this moment ....it's cyber Monday sales 🤷

@Wateribbon She's being serious, many people have learned through dna kits they were either adopted or switched at birth.

No, not a joke @Wateribbon. Not making fun or insulting. That problem generally implies adoption, marital infidelity or even switched at birth. A DNA test might shed some light on it.

One couple, the husband started accusing the wife of infidelity, until she took a test and was not genetically the mom. Their child had been switched at birth. Other times, wives may have had infidelity and sought to keep it a secret. How is that making fun or insulting?

@VeronicaJane Exactly, @Wateribbon is obviously too immature to understand sincerity.

@Wateribbon


Well, if you did get a DNA/paternity test, AND you are a match for both parents, then someone is probably mis-typed.... one parent needs to be either A or AB. Two parents with B blood type can produce a child with either B or O blood type.