APOL1 Risk Variants in Chronic Kidney Disease

The APOL1 gene encodes the apolipoprotein L1 protein, a component of innate immunity that protects against African trypanosomes. Two coding polymorphisms, designated G1 and G2, are strongly associated with increased susceptibility to chronic kidney disease in individuals of recent African ancestry. Homozygosity or compound heterozygosity for these variants elevates risk of focal segmental glomerulosclerosis, hypertensive nephropathy and progression to end-stage renal disease, yet penetrance remains incomplete. Factors such as co-inherited modifier alleles, inflammatory stimuli and cellular stress pathways—particularly those involving ion transport, endoplasmic reticulum stress and protein kinase R activation—contribute to disease onset and progression. A deeper understanding of these mechanisms has spurred development of targeted interventions, including channel blockers and modulation of stress response pathways, with potential for personalised risk stratification and therapy in high-risk populations.

Research from Nature Portfolio

Recent studies have elucidated genetic and molecular modifiers of APOL1-associated nephropathy. Investigations into a naturally occurring p.N264K missense variant reveal that its co-inheritance with the G2 risk allele markedly reduces the cytotoxicity of high-risk G1G2 and G2G2 genotypes by attenuating pore formation in renal cells, thereby decreasing disease penetrance and refining genotype–phenotype correlations. In parallel, work on APOL1 risk‐allele RNA has demonstrated that variant transcript secondary structures serve as scaffolds for activation of protein kinase R in podocytes, triggering glomerular injury and proteinuria. Crucially, these effects depend on RNA conformation rather than protein function, opening avenues for therapeutic strategies aimed at modulating RNA–protein interactions or PKR activation in APOL1-driven kidney disease.

APOL1 Risk Variants in Chronic Kidney Disease publication trend

The graph below shows the total number of articles in apol1 risk variants in chronic kidney disease across all publications each year (not limited to Nature Index journals).

Technical terms

APOL1: A gene encoding apolipoprotein L1, involved in innate immunity and trypanolytic activity.

G1 and G2 variants: Two coding polymorphisms in APOL1 associated with elevated CKD risk.

Podocyte: A specialised epithelial cell in the glomerulus essential for the renal filtration barrier.

Protein kinase R (PKR): An interferon-induced kinase activated by RNA stress, mediating translational control and cell injury.

Phenome-wide association study (PheWAS): A method to associate genetic variants with a broad spectrum of clinical phenotypes.

References

1. Strong protective effect of the APOL1 p.N264K variant against G2-associated focal segmental glomerulosclerosis and kidney disease. Nature Communications (2023).
2. APOL1-mediated monovalent cation transport contributes to APOL1-mediated podocytopathy in kidney disease. Journal of Clinical Investigation (2024).
3. Phenome-wide analysis reveals epistatic associations between APOL1 variants and chronic kidney disease and multiple other disorders. EBioMedicine (2024).
4. Innate immunity pathways regulate the nephropathy gene Apolipoprotein L1. Kidney International (2014).
5. APOL1 Risk Variants Cause Podocytes Injury through Enhancing Endoplasmic Reticulum Stress. Bioscience Reports (2018).
6. APOL1 risk allele RNA contributes to renal toxicity by activating protein kinase R. Communications Biology (2018).