Concept Map: APOL1 Nephropathy

APOL1 gene nephropathy has now emerged as a potential new entity given the linkage to African American ancestry and having these alleles that were protective against sleeping sickness and then leading to more HTN proteinuric and non proteinuric renal disease in AA.  Below is a summary concept map on this topic and how having these alleles and then a SECOND HIT concept might be necessary for disease phenotype.  There are likely two disease phenotypes- FSGS variants and then the tubular non proteinuric variants. African Americans with arterionephrosclerosis who possess two APOL1 risk variants more often lack obsolescent glomerulosclerosis and have greater degrees of (solidified and disappearing) glomerulosclerosis, thyroidization-type tubular atrophy, and microcystic tubular dilation than patients with fewer than two risk variants in the non proteinuric patient lists.  
Also, there is some emerging data that JC and BK virus might be protective for the kidney relatives of patients with APOL1 nephropathy.

References:

Pathology of Non proteinuric Renal diseases in APOL1 nephropathy
Second hit concept
Protective viruses for APOL1 nephropathy