holyshit-ayorkmint:

moansmisha:

LISTNE
IMA BOUT TO BLOW A FUCKIN GASKET
JANANAJAS
BUCKLEMMING HOLY AHIT
THEY REALLY FUCKED THIS WHPE AHOW

If Mary had type O couldn’t it be entirely possible for Dean to be type O?

Not really. Type O blood is a recessive type of gene as opposed to A/B/AB blood. If Mary is type O, then it’s possible that he can carry the recessive O blood type and pass it on to his children depending on the mother’s blood type.