Discovery of blood groups

Mr. Topesh Patle

Discovery of Blood Groups

  • The discovery of blood groups is one of the most influential breakthroughs in medical science.
  • Today, blood transfusion is a safe and common procedure, but before the 20th century, transfusion was a dangerous experiment with unpredictable results.
  • This article explains how blood groups were discovered, the scientists involved, and how this discovery changed modern medicine.

Historical Background: Before Blood Group Discovery

Early Attempts at Blood Transfusion

  • The first attempts began in the 1600s.

  • Jean-Baptiste Denis (1667) transfused lamb’s blood into humans.

  • Many patients died due to severe reactions.

  • In 1818, James Blundell performed the first successful human-to-human blood transfusion to treat postpartum hemorrhage.

However, most transfusions failed, because no one understood blood compatibility.

The Mystery

Doctors noticed:

  • Some transfusions worked perfectly

  • Others caused fever, chills, kidney failure, or immediate death

No scientific explanation was available. The idea that “all human blood is the same” was proved wrong only in the early 1900s.

Karl Landsteiner and the ABO Blood Group System (1901)

The biggest breakthrough came from Dr. Karl Landsteiner, an Austrian immunologist.

Landsteiner’s Experiment

He mixed:

  • Red blood cells of one person

  • With serum (plasma) of another person

He observed:

  • Sometimes RBCs clumped together (agglutination).

  • Sometimes no reaction occurred.

After repeated experiments, he classified blood into three groups:

  • Group A

  • Group B

  • Group O

Later in 1902, Decastello and Sturli discovered the AB blood group.

For this foundational work, Landsteiner received the 1930 Nobel Prize.

Understanding the ABO System

The ABO system is based on the presence or absence of antigens on the surface of RBCs and antibodies in the plasma.

Antigen–Antibody Relationship

Blood Group Antigens on RBCs Antibodies in Plasma Can Receive From
A A Anti-B A, O
B B Anti-A B, O
AB A and B None A, B, AB, O (universal recipient)
O None Anti-A and Anti-B O only

Scientific Importance

  • Agglutination occurs when incompatible antigens meet antibodies.

  • This causes hemolysis → kidney failure → shock → death.

  • Landsteiner’s discovery finally explained why transfusions failed earlier.

 

Discovery of the Rh Blood Group System (1937)

More than 30 years later, Landsteiner, along with Alexander Wiener, made another major discovery—the Rh factor.

What is Rh Factor?

  • Rh-positive: Rh antigen present

  • Rh-negative: Rh antigen absent

The Rh factor is extremely important in:

  • Blood transfusion

  • Pregnancy and newborn health

Hemolytic Disease of the Newborn (HDN)

If an Rh-negative mother carries an Rh-positive baby:

  • Mother forms anti-Rh antibodies

  • These antibodies attack the RBCs of the next Rh-positive baby

  • Causes severe anemia, jaundice, stillbirth, or neonatal death

Discovery of Rh factor prevented millions of deaths by allowing medical prevention using Anti-D immunoglobulin.

Extension: Discovery of Other Blood Group Systems

After ABO and Rh, researchers discovered many more blood group systems.

Today, the International Society of Blood Transfusion (ISBT) recognizes over 40 blood group systems and more than 360 antigens.

Major Clinically Important Blood Group Systems

System Year Discovered Importance
ABO 1901 Most important for transfusion
Rh 1937 HDN, major transfusion reactions
Kell 1946 Severe hemolytic disease
Duffy 1950 Associated with malaria resistance
Kidd 1951 Delayed hemolytic transfusion reactions
MNS 1927 Transfusion safety
Lewis 1946 Important in pregnancy and secretor status

Each system is based on unique antigens found on RBC membranes.

Development of Blood Typing and Cross-Matching

Landsteiner’s Rule

Serum naturally contains antibodies against the antigens not present on a person’s own RBCs.

For example:

  • Group A → anti-B antibodies

  • Group O → anti-A + anti-B

  • Group AB → no natural antibodies

Cross-Matching (Compatibility Testing)

Developed in the early 20th century:

  • Donor RBCs + recipient serum

  • Recipient RBCs + donor serum

This two-way test ensures complete safety before transfusion.

Birth of Blood Banks and Blood Storage

The discovery of anticoagulants made blood storage possible.

Key Breakthroughs in Blood Storage

  • 1914: Sodium citrate prevents clotting

  • 1916: Citrate-glucose solution increases storage time

  • 1930s: First blood banks appear in Europe and the USSR

  • World War II: Massive blood donation drives, refrigeration techniques, plasma storage

Modern Advancements

  • Component separation (RBCs, platelets, plasma, cryoprecipitate)

  • Screening for infectious diseases

  • Automated blood grouping instruments

  • Molecular (DNA-based) blood typing

 

How Blood Group Discovery Impacted Medicine

The discovery of blood groups has transformed multiple areas:

1. Safe Blood Transfusion

  • Near 100% safety when proper typing and cross-matching are done

  • Saves lives in trauma, surgery, childbirth, anemia, cancer therapy

2. Obstetrics

  • Prevention of Rh disease using Anti-D injections

3. Forensic Science

  • Blood typing used in early crime investigations and paternity testing

4. Genetics

  • Blood groups follow Mendelian inheritance

  • Helped in early genetic mapping of traits

5. Anthropology & Population Studies

  • ABO distribution varies across populations

  • Used in studying human migration and evolution

 

Interesting Scientific Facts About Blood Groups

  • O blood group is the oldest, genetically traced to early humans.

  • Type AB is the newest, believed to have formed around 900–1000 years ago through genetic mixing.

  • Bombay Blood Group (hh phenotype) was discovered in Mumbai in 1952; extremely rare and needs special donors.

  • Duffy negative blood provides resistance against Plasmodium vivax malaria.

  • Some blood groups can cause transplant rejection, not just transfusion reactions.

 

MCQs

1. Who is known as the “Father of Blood Group Discovery”?

A. Alexander Wiener
B. Karl Landsteiner
C. James Blundell
D. Jean-Baptiste Denis
Answer: B. Karl Landsteiner

2. In which year were the ABO blood groups discovered?

A. 1890
B. 1901
C. 1910
D. 1920
Answer: B. 1901

3. Who discovered the AB blood group?

A. Landsteiner and Wiener
B. Decastello and Sturli
C. Levine and Stetson
D. Boyd and Shapleigh
Answer: B. Decastello and Sturli

4. Which blood group was discovered last in the ABO system?

A. A
B. B
C. O
D. AB
Answer: D. AB

5. Landsteiner received the Nobel Prize in Physiology or Medicine in which year?

A. 1920
B. 1930
C. 1940
D. 1950
Answer: B. 1930

6. The discovery of the Rh factor was made in which year?

A. 1927
B. 1937
C. 1945
D. 1953
Answer: B. 1937

7. Rh factor was discovered by Landsteiner and _______.

A. Blundell
B. Sturli
C. Wiener
D. Levine
Answer: C. Wiener

8. The antigen responsible for Rh positivity is known as:

A. A antigen
B. B antigen
C. D antigen
D. O antigen
Answer: C. D antigen

9. Which blood group is the universal donor?

A. AB+
B. AB–
C. O+
D. O–
Answer: D. O–

10. Which blood group is the universal recipient?

A. A+
B. B+
C. AB+
D. O+
Answer: C. AB+

11. Agglutination means:

A. Breaking of RBCs
B. Clumping of RBCs
C. Dilution of plasma
D. Formation of new cells
Answer: B. Clumping of RBCs

12. Which scientist first performed human-to-human blood transfusion successfully?

A. Karl Landsteiner
B. James Blundell
C. Alexander Wiener
D. Jansky
Answer: B. James Blundell

13. The ABO blood group system is based on:

A. Enzymes
B. Antigens and antibodies
C. Hormones
D. DNA mutations
Answer: B. Antigens and antibodies

14. Who discovered the Bombay Blood Group?

A. Haldane
B. Bhende
C. Levine
D. Jansky
Answer: B. Bhende

15. When was the Bombay Blood Group discovered?

A. 1927
B. 1937
C. 1952
D. 1960
Answer: C. 1952

16. Which blood group has no antigens on RBCs?

A. A
B. B
C. AB
D. O
Answer: D. O

17. Which blood group has no antibodies in plasma?

A. A
B. B
C. AB
D. O
Answer: C. AB

18. Anti-A and anti-B antibodies are naturally found in:

A. Plasma
B. RBC membrane
C. Platelets
D. Bone marrow
Answer: A. Plasma

19. Which antigen is responsible for Hemolytic Disease of the Newborn (HDN)?

A. A
B. B
C. O
D. Rh (D antigen)
Answer: D. Rh (D antigen)

20. The person who first demonstrated the role of antibodies in transfusion reactions:

A. Levine
B. Landsteiner
C. Bhende
D. Jansky
Answer: B. Landsteiner

21. First anticoagulant used to preserve blood was:

A. Heparin
B. Sodium citrate
C. EDTA
D. Oxalate
Answer: B. Sodium citrate

22. First blood bank was established in which decade?

A. 1920s
B. 1930s
C. 1940s
D. 1950s
Answer: B. 1930s

23. ABO antibodies are mainly of which immunoglobulin class?

A. IgA
B. IgE
C. IgM
D. IgG
Answer: C. IgM

24. Rh antibodies are mainly of which immunoglobulin class?

A. IgA
B. IgG
C. IgM
D. IgE
Answer: B. IgG

25. A newborn with severe jaundice immediately after birth suggests:

A. ABO incompatibility
B. Rh incompatibility
C. Bacterial infection
D. Vitamin deficiency
Answer: B. Rh incompatibility

26. Which blood group is most common worldwide?

A. A
B. B
C. O
D. AB
Answer: C. O

27. Which blood group evolved most recently?

A. A
B. B
C. AB
D. O
Answer: C. AB

28. What did Landsteiner mix to discover blood groups?

A. Serum with platelets
B. Plasma with lymphocytes
C. Serum with RBCs
D. WBCs with RBCs
Answer: C. Serum with RBCs

29. Jansky and Moss proposed an alternative classification for blood groups based on:

A. Antibodies only
B. Cross-matching reactions
C. Platelet count
D. DNA analysis
Answer: B. Cross-matching reactions

30. Which blood group system is second most important after ABO?

A. Kell
B. Duffy
C. Rh
D. Lewis
Answer: C. Rh

31. Duffy blood group is important due to its association with:

A. Malaria resistance
B. HIV infection
C. Hemolytic anemia
D. Diabetes
Answer: A. Malaria resistance

32. The process of matching donor and recipient blood is known as:

A. Agglutination
B. Cross-matching
C. Clotting
D. Hemolysis
Answer: B. Cross-matching

33. Which blood group has both A and B antigens?

A. A
B. B
C. AB
D. O
Answer: C. AB

34. Who discovered that sodium citrate prevents blood from clotting for storage?

A. Landsteiner
B. Hustin
C. Wiener
D. Blundell
Answer: B. Hustin

35. The number of blood group systems currently recognized by ISBT is around:

A. 10
B. 20
C. 40+
D. 100+
Answer: C. 40+