Genome-wide association studies have previously shown a strong signal between a region residing on chromosome 22 centered on MYH9 and African Americans with FSGS and hypertension attributed end-stage kidney disease (H-ESKD). On July 15, 2010, Science released online a publication revealing a strong association between the same but expanded interval containing a nearby gene encoding for apolipoprotein L-1 (APOL1) in a similar group of patients.
The investigators, led by Dr. Martin Pollak, the chief of the Division of Nephrology at Boston's Beth Israel Deaconess Medical Center, reasoned that because no causal mutations have been identified in MYH9, other alleles ought to be considered. Furthermore, recent selection pressures in Africans could lead to longer patterns of linkage disequilibrium (LD). More, but previously unavailable, data from African individuals whose DNA were sequenced in the 1000 Genomes Project (www.1000genomes.org) was used to identify polymorphisms that showed large frequency differences between Africans and Europeans.