Blood Types and the Population

Blood Types and the Population

While Type O positive is the most common blood type. Not all ethnic groups have the same mix of these blood types. Hispanics, for instance, have a relatively high number of O’s, while Asians have a relatively high number of B’s. The mix of the different blood types in the U.S. populations are:

Blood Type	Caucasians	African Americans	Hispanics	Asians
O+	37%	47%	53%	39%
O-	8%	4%	4%	1%
A+	33%	24%	29%	27%
A-	7%	2%	2%	0.5%
B+	9%	18%	9%	25%
B-	2%	1%	1%	0.4%
AB+	3%	4%	2%	7%
AB-	1%	0.3%	0.2%	0.1%

(source: AABB Technical Manual)

Rare Traits

Ninety-eight percent of people suffering from sickle cell anemia are African-American. These people – most of whom are children – need to undergo regular blood transfusions. Often, they develop antibodies to the blood they receive, leading to potentially life-threatening transfusion reactions. But if they can receive blood that’s more closely matched to their own, that risk is minimized. And the best matches are found among other African-Americans.

Following is a chart of the rare blood traits and the probabilities of finding those rare traits in African-American and Caucasian blood.

Rare Trait (Negative from Factor)	Probability of Finding Rare Trait
	In Caucasian Population	In African American Population
U	None Found	1 in 250
Js(b)	None Found	1 in 319
Cr(a)	None Found	1 in 6,429
At(a)	None Found	1 in 16,400
Rh17	None Found	Not established (extremely rare)
Jk(b)	2 in 10	5 in 10
Fy(a)	3 in 10	9 in 10
Fy(b)	1 in 10	8 in 10