Key takeaways
Black kidney donors with the high-risk APOL1 genotype are about twice as likely to develop reduced kidney function as those without it.
Medical algorithms consider all Black kidney donor candidates as high risk. Less than half of major kidney transplant centers offer APOL1 testing, according to a 2019 survey .
More genetic testing will help identify lower-risk Black Americans and could increase the donor pool.
New evidence supports genetic testing of prospective Black kidney donors to see if they face elevated risks for low kidney function - a factor that could compound health issues if they donate.
The study, one of the largest and longest to follow living kidney donors, was led by UC San Francisco and Saint Louis University and published in JAMA IM on June 22. The results were presented at the 2026 American Transplant Congress in Boston.
In the study, which was funded by the National Institutes of Health (NIH), researchers followed 445 Black donors. They discovered that close to two decades after donation,15% had the APOL1 high-risk genotype, which approximately doubled their risk of reduced kidney function.
"With these data, it's hard to defend not performing genotyping for all Black donor candidates, just as it would be hard to defend not measuring blood pressure," said corresponding author Chi-yuan Hsu , MD, who is the Dr. Robert W. Schrier Distinguished Professor in Nephrology at UCSF. "Since 85% of Black kidney donors do not have this genotype, genetic testing not only offers reassurance about outcomes, it could also increase the donor pool by not classifying all Black donor candidates as high risk, which frequently happens," he added.
The majority of living kidney donations are directed to a specific individual, typically a family member.
Currently, Black patients account for approximately 30% of the kidney transplants waitlist, but only 8% to 14% of living donors. As a result, they are more likely than people of other races to rely on organs from deceased donors whose kidneys tend not to function as long.
"Enabling APOL1 testing for all Black candidates means that risk assessment becomes individualized and supports a move toward precision medicine," said co-senior author Meyeon Park , MD, MAS, Swart Family Endowed Professor in Nephrology in the UCSF School of Medicine. However, just under one-half of major kidney transplant centers offer APOL1 testing for prospective Black donors, according to a 2019 survey.
The donors in the study were drawn from the Scientific Registry of Transplant Recipients and had an average age of 38 at the time of donation. They were tracked for an average of 18.5 years, to capture the influence of the gene even before donation.
End-stage kidney disease is rare in donors, including those with high-risk APOL1
Among the Black donors, 14.7% of those with the high-risk genotype had mild-to-moderate loss of kidney function versus 6.4% of Black donors without it. The former were also more likely to have high levels of abnormal protein in their urine, indicating kidney damage. Three donors developed end-stage kidney disease, of whom one had the high-risk genotype.
Hsu said that having the high-risk APOL1 genotype should not necessarily rule out kidney donation, just as "kidney donors with hypertension or diabetes are acceptable if they are otherwise low risk."
Co-senior author Krista Lentine, MD, PhD, from the Saint Louis University Division of Nephrology and Hypertension, said the study strengthened the case for access to precision medicine tools in risk assessment. "APOL1 genetic testing adds another layer of information to the donor evaluation process, helping identify individuals who may be at higher risk while providing some reassurance for others considering living donation."
A separate conference abstract, presented on the same day by the Saint Louis University and UCSF lead researchers, suggests that recipients of donors with the high-risk genotype have increased risk for graft failure, but may still have a survival benefit over patients remaining on dialysis.
Co-Authors: Please see the paper .
Funding: National Institute of Diabetes and Digestive and Kidney Diseases (R01 DK120551 and R01 DK120551-02S1).
Disclosures: Co-author Barry I. Freedman, MD, of Wake Forest University Health Sciences, has rights to a U.S. patent relating to APOL1 genetic testing.
