# If a dad is 0 positive does his kids have to be o positive to blood type?

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• Jen
Lv 6

No, The child's blood type is determined by both parents. You can have an O child by both parents having O blood. And also if the mother is either A or B.

The RH factor (+ or - blood) can be either. Even if both parents are +, a child could be negative.

You can read more and determine possible blood types here...

http://www.biology.arizona.edu/human_bio/problem_s...

• CG
Lv 6

No. He has OO blood (one O from his Mom, one O from his Dad). O is recessive as well, so if one of his parents had passed on an A or B, he would have been AO or BO which is the equivalent of having A or B blood.

BUT, if his wife has AA or BB blood or even AO or BO blood, she could pass along the A or B to the kids who would then become A or B.

Simple answer...The only way a kid HAS to be O is for Mom AND Dad to be O.

• Jacy
Lv 4

My mom is O+ and my Dad was not. Two out of four of their children ended up being O+. It really depends on the blood type of both parents and the chromosomes that they have.

NO! Both of my parents are O+ and I'm O-. I'm the only one of eight children to be O-. This just means that both my parents carried a recessive O- gene and I happened to come up with both recessives. My Dad's Mom is also O-.

Absolutely not. The child is made from two parents, not just the father alone. The child could have his/her mothers blood type.

• 4 years ago

You mom might desire to be the two AA (homozygous) or AO (heterozygous), she would be pos or neg as nicely, because of the fact the Rh is a little extra complicated and she or he would be heterozygous or homozygous; you dad could be hetero or homozygous for the D (Rh) as nicely.