Background for the Article by L. W. Diggs, G. F. Ahmann, and J. Bibb (1933)
The incidence and significance of the sickle cell trait
Annals of Internal Medicine 7, 769 - 778
After Herrick's Case report (1), other physicians encountered similar patients with sickled cells and anemia. All of the patients were African American and genetic analysis of certain families showed that the ability of red blood cells to sickle was a dominant Mendelian trait (2). This conclusion led to considerable confusion because, as we know now, the sickle cell gene is dominant, co-dominant, or recessive depending upon which phenotypic characters are considered.
While Herrick studied a single patient, here Diggs and coworkers studied thousands of individuals in order to discern patterns that might help them understand sickle cell trait. Interestingly their analysis is genetically and statistically unsophisticated. For example, they do not know the relationship between sickle cell trait and sickle cell anemia nor do they have any idea whether some of their interesting observations are statistically significant. While this article was an important contribution to our knowledge of sickle cell trait, it is perhaps as important for what it did not discover. The seeds for several major advances lie dormant in the Diggs et al. article waiting for others to see the significance.
Lemuel W. Diggs (1900 - 1995), received his M.D. from Johns Hopkins University. He joined the medical faculty of the University of Tennessee in 1929 and nine years later helped establish the first blood bank in the South. Later in 1971, he helped Danny Thomas establish the St. Jude Children's Research Hospital in Memphis, Tennessee. It included a center for treating children with leukemia.
1. Herrick, J. B. 1910. Peculiar elongated and sickle-shaped red blood corpuscles in a case of severe anemia, Arch. Internal Med. 6, 517 - 521.
2. Taliaferro, W. H. and Huck, J. G. 1923. The inheritance of sickle-cell anemia in man, Genetics, 8, 594 - 598.