The human blood is made up of variety of ingredients; some of which are liquid and some solid. The liquid part refers to plasma that is made up of water, salts, and protein. Most people have around 4-6 liters of blood most of which is the plasma portion. The solid part is made up of red blood cells, white blood cells, and platelets. The red blood cells chiefly deliver oxygen to the various tissues in the body and remove carbon dioxide. While white blood cells act as our defense mechanism by destroying invaders and fighting infection, the platelets help in blood coagulation and speeding up healing of wounds. Although these ingredients are same in all, yet there are certain other factors that vary which ultimately gives rise to eight different blood types.
What Is Blood Typing?
Blood typing is a type of diagnostic test that perfectly determines a person’s blood type. Every individual has a different type of blood due to a unique combination of protein molecules, called antigens and antibodies that usually depends on the genes that one inherits from their parents. The antigens usually live on the surface of the red blood cells and are substances that help our body differentiate between its own cells and foreign cells, potentially the dangerous ones. It usually helps in destroying external foreign cells and infections. Whereas the antibodies are present in the blood plasma. The combination of these antigens and antibodies in your blood is what analyzes your blood type.
What Are The Various Blood Types/Groups?
The four major blood groups are chiefly based on whether or not you have two specific antigens, i.e., the A and B-type. Medically, this type of categorization is referred to as the ABO Blood Group System.
Group A: It has the A-type antigen and B-type antibody.
Group B: It has the B-type antigen and the A-type antibody.
Group AB: It has both A and B-type antigens but neither A nor B-type antibodies.
Group O: It neither has A or B-type antigens but has both A and B-type antibodies.
Apart from the usual two types of A and B antigen, there is a third type which is known as the Rh factor or the Rhesus factor (Rh) antigens. People either have this antigen on the cell surface protein making them Rh positive (Rh +ve) or do not have it in their blood plasma making them Rh negative (Rh –ve).
Based on the Rh factor, there are 8 types of blood groups. These are:
A +ve: This is one of the most common blood types and people having this blood group can give blood only to people who are A positive or AB positive and can receive from A or O blood group.
A -ve: This is quite a rare type and people having this blood type can give blood to anyone with A or AB blood type but can receive only from people with A or O blood group with a negative Rh factor.
B +ve: Another common blood group which can only be given to people who are B positive or AB positive and can receive from anyone with a B or O blood group.
B -ve: Another rare type which can be given to anyone with B or AB blood type but can receive only from people with B or O blood group with a negative Rh factor.
AB +ve: People with this rare blood type are commonly known as universal recipient and can receive blood or plasma of any type. It usually carries no antibodies in the plasma.
AB -ve: This is the rarest type of blood. People having this type of blood can receive blood plasma from anyone with a negative Rh factor.
O +ve: This is one of the most common blood types. Someone having this type of blood group can give blood to anyone but can receive only from O+ve or O-ve.
O -ve: Quite a rare blood type. Also known as “universal plasma donor, " people with this type of blood can give blood to anyone with any blood type but can receive only from a person having O-ve blood group. It usually carries no antigen in the blood plasma.
How Is The Blood Typing Test Done?
A blood typing or grouping test is much simpler and requires no special preparation like fasting. The test is usually conducted by a pathologist or doctor. The trained personnel first wraps an elastic band around the arm, causing the veins to bulge out slightly. The practitioner then sterilizes the particular area and inserts a small sterilized needle into the vein and collects the blood in a sterile vial. Once the blood is drawn, he or she removes the elastic band and asks you to put slight pressure on the puncture site to stop any leakage of blood and allow it to heal fast.
The pathologist then mixes your blood sample with antibodies that attack types A and B blood to see how it reacts. Then, the sample is analyzed to see whether or not the blood cells clump together. If blood cells stick together, it means the blood reacted with one of the antibodies. In the second step, which is usually known as back typing, the liquid part of your blood without cells (i.e., serum) is mixed with blood that is known to be type A or type B. For example, people with type A blood will have anti-B antibodies and people with type B blood will have anti-A antibodies and type O blood contains both types of antibodies.
For example, if you have type B blood, your blood sample will then be mixed with an anti-Rh serum. If your blood cells clump together in response to the anti-Rh serum, it means that you have Rh-positive blood.
Are There Any Side Effects Of The Blood Typing Test?
There are usually no reported side effects from going for a blood group or blood typing test apart from slight pain and bruising at the puncture site that too only for some time after which it usually subsides on application of an ice pack or on its own. In very rare case scenarios, there were reports of infection at the puncture site, excessive bleeding, dizziness, hematoma or multiple puncture sites to locate the vein.
What Is The Significance Of The Blood Typing Test?
Blood typing or grouping is usually done prior to a blood transfusion or when a person is planning to donate blood to someone. Originally, the different types of blood groups were discovered in 1901 by an Austrian scientist named Karl Landsteiner. Before that, doctors had a notion that everyone has same blood which ultimately led to several deaths due to blood transfusions.
After the discovery of the various blood types, doctors now know that when blood from two different people having two different blood types are mixed together, the blood plasma can coagulate or clump leading to fatal consequences. This usually happens as the antibodies of the person receiving the blood transfusion takes donor blood as foreign cell and fights the cells causing a toxic reaction within the body.
The blood grouping is especially significant in case of pregnancy. If the mother is Rh-negative and the father is Rh-positive, the new born is likely to be Rh-positive. In such scenarios, the mother needs to receive a drug called RhoGAM. This medication chiefly works keeping the mother’s body from forming antibodies that may attack the baby’s blood cells if their blood becomes mixed leading to newborn jaundice or adult jaundice in the mother.
A blood typing test is a fast and convenient way to ensure that you receive the right kind of blood during surgery or after an injury. For a blood transfusion to be 100 percent effective, it is vital for the donor and the recipient to have blood types that go together or are atleast compatible with each other. Studies show that there are several other antigens apart from the major ones (A, B, and Rh). Many minor ones are not usually detected during blood typing. If they are not detected, you may still have a reaction when receiving certain types of blood, even if the A, B, and Rh antigens are matched. Hence, It’s best when a donor and recipient are an exact match to prevent the process of crossmatching.