Your Blood Type Was Changed After 1900 — The Tartarian DNA They Replaced
Your doctor knows your blood type as four letters on a chart. A, B, AB, or O. That is all modern medicine needs from you. But before 1901, physicians read blood very differently. They could assess your constitution and predict vulnerabilities. They could infer which diseases your lineage carried. That system did not evolve into the one we use today. It was replaced by something deliberately simpler. For roughly two thousand years, Western medicine classified human beings not by letters but by constitution. The framework originated with
Hippocrates around 400 BC and was refined by Galen in the second century. It divided people into four primary types based on the balance of bodily fluids. Sanguine. Choleric. Melancholic. Phlegmatic. Each type had a distinct physical appearance, a distinct personality, and critically, a distinct pattern of disease vulnerability. A sanguine person, blood dominant, ran warm and wet. They presented with ruddy complexions, optimistic dispositions, and susceptibility to fevers and inflammatory conditions. A melancholic person, dominated
by black bile, ran cold and dry. They were lean, dark complexioned, prone to depression and digestive disorders. This was not folk medicine. This was the operating framework of every university trained physician in Europe for centuries. Avicenna’s Canon of Medicine, written in the eleventh century, extended it across the Islamic world. It was taught at Oxford, at Padua, at Bologna, at every major medical institution on three continents. The system persisted not because people were ignorant. It persisted because physicians kept observing that
it worked. And it was diagnostic in ways we have largely forgotten. Your physician would assess your constitutional type and prescribe accordingly. Different diets. Different remedies. Different warnings. What would harm one constitution would heal another. The system treated you as an individual shaped by lineage and environment, not as a universal body. In the eighteenth century, physicians named Stahl and Hoffman tried to refine this even further. They proposed that temperament depended on three specific factors. The constitution of
the blood itself. The porosity of body tissue. And the width of blood vessels. They were trying to isolate what the blood contained that made people different from one another. They were getting closer to something. And then the entire line of inquiry was abandoned. Not because it was disproven through rigorous experiment. Because it was replaced by something faster. In 1901, a thirty two year old pathologist named Karl Landsteiner sat in his laboratory at the University of Vienna with six blood samples. His own and five from his colleagues. He mixed serum

from one person with red blood cells from another and watched what happened. Some samples clumped together. Others did not. In a single series of observations, he identified three distinct groups. He called them A, B, and C. Group C was later renamed O. The following year, his students Adriano Sturli and Alfred von Decastello found a fourth group, AB. That was it. Four letters. The entire spectrum of human blood variation, reduced to a surface antigen test. Before Landsteiner, physicians believed all human blood was essentially identical. When transfusions failed,
they blamed the syringe, the technique, the patient’s weakness. Never the blood itself. Landsteiner changed that. He made safe transfusion possible. He won the Nobel Prize in 1930. None of that is in dispute. What is worth examining is the speed and totality of the replacement. Not just what Landsteiner discovered, but what was discarded in the process. The constitutional framework was not debated, refined, or integrated into new findings. It was classified as pre-scientific and removed from medical education entirely. And
the institutional architecture behind that removal is documented. It is not hidden. It is just rarely discussed in sequence. Abraham Flexner was not a physician. He held a bachelor’s degree in classics from Johns Hopkins. In 1910, funded by the Carnegie Foundation, he published a report evaluating every medical school in America. His conclusion was devastating. Too many schools. Too many doctors. Too many competing philosophies. His recommendation was standardization. Within two decades, more than half of all American medical schools had closed.
One hundred and sixty institutions in 1904. Only sixty six by 1935. Schools teaching homeopathy, naturopathy, herbal medicine, electrotherapy, and constitutional approaches were systematically eliminated. The diversity of American medicine, which had included at least six competing philosophies, was reduced to one. In 1900, there were twenty two homeopathic medical schools in America. By 1923, only two remained. By 1950, none. The Rockefeller and Carnegie Foundations directed their funding exclusively to schools that adhered to the biomedical model. If your
school taught constitutional medicine or individualized treatment based on patient temperament, your funding disappeared. If your school taught standardized diagnosis and pharmaceutical intervention, the money arrived. Now here is the part that no one mentions in the same conversation. Karl Landsteiner left Vienna in 1923 and moved to New York. He spent the rest of his career at the Rockefeller Institute for Medical Research. That institute was organized and directed by Simon Flexner. Abraham Flexner’s brother. The man who standardized
American medicine and the man who simplified human blood worked in the same institutional network, funded by the same family, operating toward the same goal. Standardization. Reduction. Classification. The complex, individualized, constitutionally aware medical framework was replaced by a system that sorts every human on earth into four categories. I am not arguing this was a conspiracy. I am saying it was a pattern. And patterns deserve scrutiny. Let me be honest about something that slowed this research down.

I spent three weeks reading nineteenth century medical texts expecting to find the constitutional blood system described as a serious diagnostic framework that was suppressed. What I actually found was more complicated. The humoral system was genuinely wrong about its mechanisms. Black bile, as Galen described it, does not exist as a distinct bodily fluid. Bloodletting killed people, including quite possibly George Washington. The old system’s explanations for why people got sick were often incorrect. And Landsteiner’s discovery was not a minor refinement. It was a breakthrough
that saved millions of lives during the First World War alone. I almost stopped writing this script because the mainstream narrative, that an outdated system was replaced by a better one, is partly true. But partly true is not the same as completely true. Because the old system’s outputs, what it predicted about who would get sick and why, have been quietly validated by modern genetics. The mechanisms were wrong. The observations were not. Here is what twenty first century research has confirmed. Your ABO blood type is not just a
transfusion label. It is a disease map. Type O individuals have a sixty six percent reduction in odds of developing severe falciparum malaria. That finding was published in the Proceedings of the National Academy of Sciences in 2007. But type O also increases vulnerability to severe cholera. Researchers studying the Ganges Delta found that cholera’s centuries of devastation there correspond to unusually low rates of type O blood in the population. The disease shaped the survivors. Type A increases susceptibility to smallpox, stomach cancer, and ovarian cancer.
Type B correlates with higher rates of gonorrhea, tuberculosis, and certain bacterial infections. Type AB increases cognitive impairment risk and vulnerability to E. coli. These are not fringe findings. They are published in the American Society of Hematology’s journal Blood, in BioMed Research International, in PNAS. Peer reviewed. Replicated. Sitting in the literature for anyone to read. Your blood type tells a story about what epidemic environment your ancestors survived. It is a record written in antigens. If your family carries type O, somewhere in your lineage,
malaria was the greater threat. If your family carries type A, cholera was the killer that shaped your survival. The sanguine constitution, blood dominant, warm and wet, prone to fevers. The old physicians were describing disease susceptibility patterns that modern immunology has only recently quantified. They did not know the word antigen. But they were watching the same outcomes. They were mapping the same vulnerabilities. They were reading blood the way a geologist reads rock layers, as a record of what came before. During the First World War, a Polish physician
named Ludwik Hirszfeld and his wife Hanna were stationed with Allied forces in Thessaloniki, Greece. They had access to soldiers from across three continents. Over several months, they drew blood from more than eight thousand men representing at least sixteen ethnic groups. What they found was striking. Type A predominated in Western Europeans. Among English soldiers, forty six percent were type A and only ten percent type B. Among Indian soldiers, those numbers reversed. Twenty seven percent type A, forty seven percent type B. The Hirszfelds
published their findings in The Lancet in 1919 and proposed that blood types mapped onto geographic and ethnic origin. They used a term that now makes historians uncomfortable. Biochemical races. They were attempting to do with modern serology exactly what the old constitutional system had done with humoral theory. Connect blood to lineage. Within fifteen years, the German Society for Blood Group Science had weaponized their data. Type A’s predominance in Germany was cited as proof of Aryan racial superiority. In 1935, the Nazi Reichstag passed the Blutgesetz,
the Law for the Protection of German Blood and German Honor. Blood type as legal identity. Blood as the basis for who could marry, who could live, who would be eliminated. The cruelest detail is this. Ludwik Hirszfeld was Jewish. In 1941, he and Hanna were forced into the Warsaw ghetto. The man whose research had been twisted into a weapon of racial purity was now imprisoned by that weapon. He fought typhus epidemics in the ghetto. He gave secret medical lectures to students who would not survive the war. He wrote later,
with precision that carries its own grief, that he wished to separate himself from those who link blood types to the mystique of race. He survived. His discovery did not emerge unscathed. Blood became the most dangerous classification system of the twentieth century. Not because of what it measured, but because of what people decided it meant. And then there are the Basques. A population living in the western Pyrenees between Spain and France. They speak Euskara, a language unrelated to any other living language in Europe.
Genetically, they are among the most isolated populations on the continent. And they have the highest frequency of Rh negative blood anywhere on earth. Thirty to thirty five percent, compared to the European average of roughly sixteen percent. They also carry the highest concentration of type O blood, over fifty percent, with almost no type B. Science offers hypotheses. The founder effect. Genetic drift in an isolated mountain population. Possible resistance to the parasite that causes toxoplasmosis. But no hypothesis has been definitively demonstrated. The European Journal
of Human Genetics published a genomic analysis in 2018 and concluded that the causes of the Basque Rh negative frequency remain unresolved. Here is what makes this more than a genetic curiosity. Before 1968, before the invention of RhoGAM, an Rh negative mother carrying an Rh positive baby faced devastating odds. Her immune system would attack the baby’s blood. Miscarriage. Stillbirth. Fatal anemia in the newborn. A population with thirty five percent Rh negative frequency should have been selected out of existence by their own biology. They were not. They persisted for
thousands of years in those mountains, speaking a language no one else speaks, carrying blood no one can fully explain. Other regions with unusually high Rh negative frequency include the Atlas Mountains of Morocco, the Canary Islands, and parts of Ireland and Scotland. These are populations associated with pre-Indo-European ancestry. Ancient peoples who were already there when the migrations came. The migrations that supposedly explain everything about modern genetic distribution somehow do not explain this. Isolated populations on opposite
sides of the Mediterranean carrying the same blood signature, speaking unrelated languages, sharing no recorded contact. The standard explanation is coincidence plus isolation. But coincidence is doing extraordinary work in that sentence. The modern blood classification system acknowledges forty eight distinct blood group systems as of 2025. Most people know one. The ABO system tells you what antigens sit on the surface of your red blood cells. It does not tell you what those antigens do beyond transfusion compatibility. It does not tell you
which diseases your lineage survived. It does not tell you why your blood clusters geographically with populations that share no language, no culture, and no obvious migration path. The old system tried to tell you those things. It was wrong about the mechanisms. It was not wrong about the pattern. Your constitution, your temperament, your blood, these were treated as a single story. A story about who you were, where your people came from, and what would threaten your body. That story was replaced by a letter on a card. A, B, AB, or O. Clean.
Universal. Standardized. And stripped of everything the old physicians spent two millennia trying to understand. I keep circling the same question. What was the constitutional system actually tracking that modern medicine has chosen not to pursue? If blood type genuinely predicts disease susceptibility, and it does, peer reviewed and published, then why is that information not part of standard medical practice? Why does your doctor know your blood type but never mention what it means for your cancer risk, your infection vulnerability,
your ancestral disease environment? Why do forty eight blood group systems exist but only one gets discussed? The answer might be simple. Perhaps it is too complex. Perhaps medicine prioritizes what is actionable over what is merely interesting. Or perhaps the system that replaced the old one was never designed to tell you more about yourself. Perhaps it was designed to tell you less. To sort you into categories useful for institutions. Transfusion compatibility. Paternity testing. Forensic identification. Functions that serve the system, not the individual. The old physicians
asked, who is this person and what do they carry in their blood? The new system asks, what letter do we assign them for the database? Those are fundamentally different questions. And only one of them was ever interested in the answer. Your blood type is one of the oldest pieces of biological data your body carries. It connects you to ancestors you will never meet, to epidemics you will never face, to a lineage the modern system has no interest in helping you trace. Forty eight blood group systems. Centuries of epidemic selection pressure encoded in your
cells. Disease vulnerabilities that track with geographic origin in ways that accepted migration models cannot fully account for. And you have been given a letter. One letter. As if that letter captures what two thousand years of physicians were trying to understand. The old system said blood was a story. The new system says blood is a classification. The story did not stop being true just because we stopped reading it. And somewhere in the gap between what your blood carries and what you have been told it means, there are questions. Questions
that modern medicine has never been willing to ask. Not because the answers are unavailable. Because asking them leads to places that standardized systems cannot afford to go.
