Can an O positive parents have an O negative child?
Suffice it to say that A, B and AB are dominant over O, so children will be type O only if they inherit O-type genes from both parents. In the very simplest terms, you inherit a positive or a negative Rh type from each parent. So, you could wind up with two positives, two negatives or a positive-negative mix.
He is AB blood type but carries the O version of the blood type gene. Now let's imagine that he has a child with a woman who has an A and an O gene. She is A blood type but like the father, also carries an O version of the ABO gene. And this is just the most common way an AB parent can have an O child.
- But someone who has a B and an O version only makes the B protein. They are B blood type but can pass the O onto their kids. So two B parents can make an O child if both parents are BO. Each parent has a 50% chance of passing down the O gene.
- The Rhesus (Rh) system divides each of these into either a positive of negative, creating eight blood types: O-, O+, B-, B+, A-, A+, AB-, AB+. The most common blood type in South Africa is O+, and the most rare is AB-.
- Type O-negative blood is called the universal donor type because it is compatible with any blood type. Type AB-positive blood is called the universal recipient type because a person who has it can receive blood of any type.
Two parents with B blood type can produce a child with either B or O blood type. One parent with A and another with B can produce a child with A, B, AB or O blood types. If one parent has A and another has AB, they can either produce a child with A, B or AB blood types.
- Suffice it to say that A, B and AB are dominant over O, so children will be type O only if they inherit O-type genes from both parents. In the very simplest terms, you inherit a positive or a negative Rh type from each parent. So, you could wind up with two positives, two negatives or a positive-negative mix.
- O positive is the most common blood type and most likely to be transfused. O negative donors are the “Universal Donor.” People with O negative blood are universal red blood cell donors. This means that their red blood cells can be transfused to any blood type.
- That means each child of these parents has a 1 in 8 chance to have a baby with an O- blood type. Each of their kids will also have a 3 in 8 chance of having A+, a 3 in 8 chance of being O+, and a 1 in 8 chance for being A-. An A+ parent and an O+ parent can definitely have an O- child.
Updated: 9th October 2018