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I’m a freckled redhead with type B blood. I am my own race! The superior one.

...the genes for blood type reside on chromosome 9 (this was in Matt Ridley's "Genome") and the genetic sequence that produces type A are nearly the same as type O (which produces no distinctive protein) -- type O is the same sequence as type A, with the first base pair (or maybe it was the first "word" of three base pairs; I'm too lazy to look) missing. Type A and type B are very similar, but produce different proteins. Type B is about 15 per cent of the population; type A is 40 per cent, as is type O; type AB is the result of having the A and B coding on the same chromosome and is about 5 per cent of the population.

And there's more:

More Biochemistry and "Bombay phenotype"
by Robert J. Huskey
An interesting situation arises when an individual is not able to make the "H" antigen. Such a person cannot produce the "H" antigen and even if the "A" or "B" enzymes are present, cannot make "A" or "B" antigen since there is no precursor for the antigens to act upon. An individual who cannot produce the "H" antigen will appear to have blood type "O" since this blood type is a negative category (not-A, not-B, not-A and not-B). This was first documented in Bombay and has become known as the Bombay phenotype and has been exploited on the popular soap opera General Hospital.

To my eye type A seems to be the original bloodtype, producing the others through mutation. The exceptions may be the MN bloodtype system, which comes from the Indian subcontinent, and are analogous (but not the same thing as) to A & B (codominant), AFAIK (it's often difficult to find anything about the MN system, which is in a very small number of people worldwide). Strange, isn't it, that a completely unrelated bloodtype system exists (still exists? recently sprang into existence?) after centuries, even millennia, of contact, intermarriage, and commerce, all over the world?

Somehow the % for type O blood doesn’t make sense. I thought that more than half the population had type A blood.

Exactly. I’m native american, o-positive, and far from being a ginger.