Presentation: Potential living related kidney donor of African heritage
Individuals with both parents of African, African-American, Caribbean or Brazilian heritage have an increased risk of chronic kidney disease and progression to kidney failure. Part of this risk is explained by the presence of two apolipoprotein L1 (APOL1) high-risk gene variants (G1/G2) and therefore genomic testing is relevant to potential living kidney donors from these backgrounds.
Example clinical scenario
A 45-year-old Nigerian man presents to the renal transplant service as a potential living related kidney donor for his brother. There is no additional family history of kidney disease, although his brother’s primary renal diagnosis is unknown as he first presented with kidney failure. Initial biochemical, tissue type and antibody testing is supportive of him as a potential kidney donor.
When to consider genomic testing
Request testing for potential living kidney donors where all the following criteria are met:
- Both the individual’s parents have, or are likely to have, African, African-American, Caribbean or Brazilian heritage.
- The individual has undergone counselling and understands the implications of testing and has provided consent.
- The potential donor has undergone basic biochemical, tissue type and antibody testing but has not yet had other investigations such as CT angiography.
What do you need to do?
- Consult the National Genomic Test Directory. From here you can access the rare and inherited disease eligibility criteria for information about individual tests and their associated eligibility criteria. You can also access a spreadsheet of all available tests.
- For information about how to arrange testing in Wales, Scotland or Northern Ireland, see Genomic testing in the devolved nations.
- For information about the genes that are included on different gene panels, see the NHS Genomic Medicine Service (GMS) Signed Off Panels Resource.
- In this case, it is likely that R446 APOL1 kidney donor testing is the most appropriate indication. This is a single gene test for those who meet the above criteria.
- This test does not use whole genome sequencing (WGS), so you should use your local Genomic Laboratory Hub test order form and consent (record of discussion) forms.
- Most tests are DNA based, and an EDTA sample (typically a purple-topped tube) is required. There are a few tests for which a different type of tube is used; see Samples for genomic testing in rare disease.
- If you are discussing genomics concepts with your patients, you may find it helpful to use the visual communication aids for genomics conversations.
- Information about patient eligibility and test indications were correct at the time of writing. When requesting a test, please refer to the National Genomic Test Directory to confirm the right test for your patient.
Resources
For clinicians
- British Transplant Society: APOL1 testing in potential living kidney donors
- Genomics England: NHS Genomic Medicine Service (GMS) signed off panels resource
- NHS England: National Genomic Test Directory
For patients
- British Transplantation Society: APOL1 gene testing for people who want to donate a kidney