Naturally occurring antibodies occur in most species and vary in their pathological significance, i.e. There are two types of antibodies to blood group antigens naturally occurring antibodies and antibodies acquired after exposure to the blood group antigen. Knowledge of blood types in the different species is important as transfusion of incompatible blood (the donor animal has a different blood type from the recipient animal) can result in severe hemolytic transfusion reactions and even death, in some instances. In humans, there is the ABO system of blood types, whereas animals have a variety of different blood types. If a person has the genes -, the Rh factor will be negative.Ī baby receives one gene from the father and one from the mother.Blood types (or groups) are determined by specific antigens found on the surface of erythrocytes. If a person has the genes + -, the Rh factor will also be positive.

If a person has the genes + +, the Rh factor in the blood will be positive. The Rh-positive gene is dominant (stronger) and even when paired with an Rh-negative gene, the positive gene takes over. Rh factors follow a common pattern of genetic inheritance.

A baby may have the blood type and Rh factor of either parent, or a combination of both parents.

The following are the possible combinations of blood types with the Rh factors: If there is no Rh factor protein, the person is Rh- negative. If the Rh factor protein is present on the cells, the person is Rh-positive. The Rh factor is a protein that is found on the covering of the red blood cells. The blood type is found as proteins on red blood cells and in body fluids. The blood type and the Rh factor simply mean that a person's blood has certain specific characteristics. Every person has a blood type, (O, A, B, or AB) and an Rh factor, either positive or negative.

What is the most common blood type