Question

What is 0+ blood type?

Answer 1

It tells you two things:

1. Your red blood cells do not contain type A or B antigens
2. Your red blood cells do contain Rh factor

Explanation:

Blood type (A, B, AB, and O) is determined by specific proteins (i.e. antigens) which are found on all of your red blood cells. There are two main types of antigens on your red blood cells:

Type A antigens
Type B antigens

These antigens are made from specific genes that you get from your parents. These genes create an enzyme which alters a specific protein on newly made red blood cells.

If you have type A blood, then the enzyme modifies your red blood cells to express what we call "type A antigens". If you have type B blood, then the enzyme modifies your red blood cells to express "type B antigens."

If you have type O blood, then the enzyme is inactive and the red blood cells do not have either type A or B antigens. This does not make the red blood cell defective, it just means that the red blood cell does not have these antigens on it.

All of this is important because a person's blood type determines what they may receive in a blood transfusion. If a doctor were to give them the wrong type of blood, it could potentially kill them.

So what makes someone O+ or O-? The answer is something called Rh factor.

Rh factor is just another protein on red blood cells. Some people have Rh factor and some people don't. If you do have Rh factor, you are Rh+. If you don't then you are Rh-. This has implications with childbirth, but that is a discussion for another time.

So let's combine what we have learned here:

If someone is O+, that means 2 things:

1. Their red blood cells do not have type A or type B antigens
2. Their red blood cells do contain Rh factor

Hope this helps!

~AP