The APOLLO study is being done in an attempt to improve outcomes after kidney transplantation and to improve the safety of living kidney donation based upon variation in the apolipoprotein L1 gene (APOL1). Genes control what is inherited from a family, such as eye color or blood type. Variation in APOL1 can cause kidney disease. African Americans, Afro-Caribbeans, Hispanic Blacks, and Africans are more likely to have the APOL1 gene variants that cause kidney disease. APOLLO will test DNA from kidney donors and recipients of kidney transplants for APOL1 to determine effects on kidney transplant-related outcomes.

The National Institutes of Health (NIH)-sponsored collaborative APOL1 Long-term Kidney Transplantation Outcomes Network (APOLLO) is charged with prospectively assessing the effects of renal-risk variants (RRVs) in the apolipoprotein L1 gene (APOL1) on outcomes for kidneys from donors with recent African ancestry and the recipients of their kidneys, after deceased- and living-donor renal transplantation. For the purposes of APOLLO, recent African ancestry is defined as individuals with similar genetic make-up to those currently residing in Africa. APOLLO will also study the impact of APOL1 RRVs on the health of living kidney donors with recent African ancestry.

Inclusion Criteria for Living Donors:

• Living kidney donors with self-reported recent African ancestry (defined as African American, Afro-Caribbean, Hispanic black or African) will be eligible for inclusion.

Exclusion Criteria for Living Donors:

• Participants who are unable or unwilling to provide informed consent.

Enrollment and bio sample collection from deceased donors at OPOs ended on May 31, 2023 and recruiting kidney transplant recipients ended on June 15, 2023.

Phase II started on 9/1/2023 and only Living Donors will be recruited for an additional 2 years.

Thirteen APOLLO Clinical Centers (CCs) will prospectively enroll eligible living kidney donors and recipients of kidney transplants from eligible living and deceased kidney donors at all transplant programs in the continental United States including Puerto Rico. The APOLLO Scientific and Data Research Center (SDRC or Coordinating Center) will support and participate in studies determining the impact of donor and recipient APOL1 genotypes on kidney transplant outcomes in recipients of a kidney transplant from a donor with recent African ancestry, and follow African ancestry living kidney donors for changes in vital status, kidney function and proteinuria. In this protocol, recent African ancestry is broadly defined as African American, Afro-Caribbean, Hispanic black, and African.

Study participants will have the option of receiving their APOL1 genotype test result from a Clinical Laboratory Improvement Amendments (CLIA) research lab. Deceased donor family decision makers will also have the option of receiving their loved one's APOL1 genotype test result from a CLIA research lab. Results will be made available after enrollment is complete.Those who wish to receive these results will have been informed of benefits and risks of requesting and receiving this information prior to consenting to participate in APOLLO and again at the time of requesting test results. Info graphics to aid in the decision process for requesting Individual Participant Data (IPD) are provided at the time of consent and on the APOLLO website. Prior to sending IPD, participants and deceased donor family decision makers will be asked to verify that they received and understand the information. They will be able to ask questions to local study staff or the Coordinating Center.

Approximately 3 years after enrollment begins (once all testing is performed at once). Results will be available for 12 months.

Requests for return of IPD will be made via the APOLLO website. Individual letters containing IPD and explanations of results will come via the United States Postal Service.