The racist “one drop rule” influencing science: it is time to stop teaching “race corrections” in medicine

Abstract

Glomerular filtration rate (GFR) is a key index of renal function. The classic method for assessing GFR is the clearance of inulin. Several current methods using isotopic (125I-iothalamate, 51Cr-EDTA, or 99Tc-DTPA) or nonisotopic (iohexol or iothalamate) markers are available. Clinically, GFR is estimated (eGFR) from serum creatinine or cystatin C levels. Estimated GFR based on creatinine and/or cystatin are less accurate than measured GFR. The creatinine-based equations calculate higher eGFR values (suggesting better kidney function) for black individuals. This upward adjustment for all black individuals is embedded in eGFR calculations on the belief of higher serum creatinine concentrations among black individuals than among white individuals. Thus “race-corrected” eGFR has become a widely accepted and scientifically valid procedure. However, race is not a genetic or biological category. Rather, race is a social construction defined by region-specific cultural and historical ideas. Furthermore, there is no accepted scientific method for classifying people as black or white individuals. Studies typically rely on self-identification of race. However, any person in the United States with any known black ancestry is considered to be a black individual. This is known as the “one-drop rule,” meaning that a single drop of “black blood” makes anyone a black individual. It does not matter if an individual has 50%, 25%, 5%, or 0.5% African ancestry. The limited accuracy and reliability of this approach would not be allowed for any other scientific variable. Admixture and migration have produced such broad variations that race categories should not be used as experimental variables.

Retaining Race in Chronic Kidney Disease Diagnosis and Treatment

“…Although some papers are more circumspect [ 20 - 23 ], the systematic review identified fifty reviews, editorials, and commentaries in peer-reviewed journals [ 10 , 13 , 19 , 24 - 70 ] that argued for the abolition of race-based GFR cr estimation because Black race is: 1) a societal rather than biological construct [ 10 , 15 , 24 - 31 , 34 - 45 , 48 - 52 , 55 , 58 , 60 - 67 , 69 , 70 ]; 2) an imprecise proxy for genetic ancestry [ 13 , 24 - 26 , 29 , 31 , 43 , 44 , 46 - 50 , 60 - 65 , 67 , 70 ]; 3) poorly defined [ 10 , 13 , 19 , 34 , 39 , 43 , 44 , 48 - 52 , 55 , 62 , 63 , 67 - 69 ]; and 4) heterogeneous [ 10 , 26 , 29 , 30 , 34 , 35 , 44 , 46 , 52 , 66 , 67 ]. These articles also declared that the race correction: 5) lacked a physiological explanation [ 10 , 25 - 27 , 29 - 31 , 37 , …”

“…Delanaye et al’s claim that “skin color does not influence GFR or serum creatinine in a biological sense” [ 25 ] implies the existence of an argument never made. Similarly, a one-drop rule was never proposed for identifying Blacks in estimating eGFR cr [ 48 , 54 ].…”

How Abolition of Race-Based Medicine Is Necessary to American Health Justice

“…The MDRD and CKD-EPI equations, which are now widely used to assess kidney function, include "race corrections" that result in 21% and 16% higher estimates, respectively, for African Americans alone. 15,16,17,18 These specious estimates can result in years' delayed referrals to kidney specialty care and kidney transplant evaluations for Black patients compared to other racial groups. 19 Debate about abandoning race correction has transpired against a backdrop of some of the most profound racial disparities in medicine.…”

African American/black race, Apolipoprotein L1, and the indirect glomerular filtration measure serum creatinine among persons living with HIV

“…Race and ethnicity are both social constructs with no biologic or scientific process by which an individual is classified as belonging to a specific racial group [9][10][11]. This is problematic as the historical basis of classifying individuals as AAB vs. non-AAB is rooted in slavery and segregation, and fails to account for the underlying diversity in prevalence of African or European ancestry but rather designates any person with any degree of AAB ancestry as an AAB individual, a policy known as the 'one drop rule' [12,13]. The challenges associated with this binary classification are particularly salient when considering the 2020 Census results in which the United States population is more diverse than seen in any previous census with greater proportions of individuals identifying as multiracial [14].…”