Quiz 2 Flashcards
Early Medical Perceptions (1910-1950)
Sickle cell anemia was first identified in 1910 by James B. Herrick, who observed sickle-shaped red blood cells in a Black patient. Early physicians, influenced by prevailing racial theories, categorized it as a hereditary disease exclusive to African Americans, termed a “disease of Negro blood.”
Mendelian Dominance Theory
Early 20th-century physicians believed sickle cell anemia followed Mendelian dominant inheritance, implying interracial marriages could spread the disease to white populations. This assumption was used to reinforce racial segregation and justify eugenics policies.
Emmel’s Blood Test (1917)
Victor Emmel developed a test to detect sickle cells, which became a primary diagnostic tool. It was used to confirm “latent sickling” even in asymptomatic individuals. This test reinforced the racialization of the disease, with physicians using it to trace supposed “Negro ancestry” in white patients.
Electrophoresis and Molecular Advances (Post-1950)
The introduction of electrophoresis by scientists like Linus Pauling transformed the understanding of sickle cell anemia. It identified the disease as a “molecular disease” caused by abnormal hemoglobin (Hemoglobin S). This marked a shift from racialized interpretations to a biochemical perspective.
Racialization of Sickle Cell Anemia
In the early 20th century, sickle cell anemia was used as a tool to reinforce racial hierarchies. Miscegenation was portrayed as a public health threat, with the disease framed as evidence of the dangers of racial mixing.
Segregation Policies
Blood donation practices during World War II highlighted the persistence of racial biases. The American Red Cross segregated blood from Black and white donors, despite no scientific basis for doing so.
Shift in Racial Narrative
By the mid-20th century, researchers like J.V. Neel demonstrated that sickle cell anemia followed a recessive inheritance pattern and was not exclusive to African Americans. This helped debunk earlier racialized views, but biases persisted in societal and medical discourse.
The Rise of Molecular Biology
Pauling’s work in the 1940s identified sickle cell anemia as a molecular disease, characterized by structural abnormalities in hemoglobin. This laid the groundwork for understanding hemoglobinopathies and advanced the field of biochemical genetics.
Implications for Medical Science
Molecular diagnostics redefined disease identity, moving away from subjective racial interpretations to objective biochemical markers. This also aligned with postwar optimism in biomedical engineering and the promise of molecular cures.
Cultural and Clinical Misunderstandings
Despite advancements, the societal understanding of sickle cell anemia remained steeped in racial prejudices. Misdiagnoses and overemphasis on racial identity overshadowed the focus on patient care.
Broader Significance:
The history of sickle cell anemia underscores the dual role of technology in medicine: it can either reinforce societal biases or challenge them through scientific inquiry. It also highlights the evolving relationship between science, culture, and identity
James B. Herrick
In 1910 discovered “peculiar, elongated and sickle-shaped red in a Negro patient with severe anemia
Verne Mason and John Huck
-After Herrick’s observations, used a new blood analysis technique to hypothesize that this was a hereditary disorder occurring only in black people
-Argued according to the Mendelian laws regulating a dominant trait, not sex-linked = it could be transmitted from one parent to his or her offspring independent of the other parent’s genetic endowment
-meant that interracial marriages would probably spread the blood disease outward from the black population into negligent whites
The concept of blood
ideas about heredity/kin/clan/ and community in the same way that the term genes does today
In the late 1940s geneticist J.V. Neel and physical chemist Linus Pauling used new blood analysis techniques to put forth a new thesis
-Used new methods of electrophoretic analysis, focused on hemoglobin -> RBC sickled not because of black blood but cause of abnormal hemoglobin -> thrombosis, infections, painful crises, death
-Not a Mendelian dominant disorder but a disorder that depended on the inheritance of recessive traits from both parents (currently accepted view)
-Marry outward wouldn’t spread disease and might reduce incidence
-now known as molecular disease and scientists hoped for molecular cure one day
-electrophoresis revealed black people as part of biochemical diversity of humankind
Miscegenation
-Throughout the 1920s-1940s miscegenation was characterized as the key reason for the appearance of sickled cells in “whites” and as the primary vehicle of transmission of black blood and this disease
Black Disease and Black Blood
-In the late nineteenth and early twentieth centuries, the new mobility of African Americans stirred discussions about Black Health in all regions/professions e.g. tuberculosis, syphilis
-Though essential for the medical examiner to investigate ancestry/mixed blood, argued science not prejudice supported findings
-The close social proximity and economic relationships of blacks was one factor that fed anxiety about the problem of black diseases
-some argued poverty and lack of access to medical information explained differences
-others thought inferior physical and moral constitution of black race
-thought black people brought disease from Africa
Emmel’s Blood Test
-A ring of petroleum jelly could be drawn on a sterile glass slide, a fresh drop of the patient’s blood was brought to rest in the center of the ring, and then the first slide was covered in an air-tight chamber and held it at room temperature. After a few hours Emmel found a “great abundance of these [sickled] structures” (test induced cells to sickle)
-Suggested technique diagnosed potenial/latent disease, sicklemia to become a full-fledged anemia (Today sicklemia = technologically defined trait, sickle cell anemia = clinical disease)
Social implications
-In the early 1940s the disease provided rich biological material for defenses of segregation and for restrictions on intermarriage
-Black Americans should not be admitted into the military
-segregated black blood donations
Even as mainstream medical journals endorsed Emmel’s test and its severe implications criticisms appeared
Others turned away from Mendelian law, interest in new population genetics, natural mutations, gene pools, evolutionary theory (other than racial crossing)
Different theories following Emmel before Electrophoresis
-some physicians tried to convince colleagues that appendicitis, mitral insufficiency, TB and other diseases were actually sickle cell anemia
-pediatricians labeled sickle cell anemia a childhood disease
If Emmel’s technique symbolized the racial politics of pre-World War II America, then electrophoresis symbolized a new set of technological ideals and eugenic possibilites for dealing with race in America
-Dunn asked, “What should happen if a cure for sickle-cell anemia is found and the homozygotes which now die should be enabled to contribute their quota of children and genes to succeeding generations
-Dunn believed we should use technologies not to cure patients but engineer society
