our baby is A+ and me and my wife are O+ but a DNA test proved he was ours can someone explain this to me how?

Answer 1

Actually, blood types are codominant. If you are OO and your wife is OO, you might want to check your postman's blood type. the only way to get a child with A is for either you or your wife to carry the gene for A, in case your blood type would be A (or AO), not O. Someone screwed up somewhere

*sigh* If you are NOT a geneticist, do NOT answer this question. You just confuse everyone and cause chaos.

Answer 2

Ummm. if your wife was pregnant with him, he's hers. If you doubt your paternity, do a DNA test. But O is the universal blood type. I'm an O too. A, B, AB, and those other kinds are recessive blood types. (See Mendals square for a better explination). Just like say, you and your wife have brown hair and say... green eyes, doesn't mean the baby will. the baby may have hazel eyes ( pretty common color, dominant gene), and red hair ( recessive gene, don't see too many red-heads do you?) Anyway, that's the best I can do. Sorry if I confused you more! :-)

Answer 3

Two O+ parents can't have an A+ baby, have you considered that you or your wife were given the wrong blood typing result at some point?

http://www.biology.arizona.edu/Human_Bio/problem_sets/blood_types/markers.html

In any case it is easier to imagine screwing up a blood typing then screwing up DNA.

Answer 4

I'm wondering why you had a DNA test.
It's possible some relative has that type and the baby inherited that, as well as height, eye color, hair color, or any other genetic trait. It's always a roll of the dice when it comes to genes.

Answer 5

Here ya go:
http://www.drgreene.com/21_1003.html

Parents with the same blood type can produce another type altogether.

(later post): I actually just looked at that closely- either results got mixed up or it isn't yours- what did the Doc say?