title: Absence of APOL1 risk variants protects against HIV-associated nephropathy in the Ethiopian population.
abstract: BACKGROUND
  Susceptibility to end-stage kidney disease (ESKD) among HIV-infected Americans of African ancestral heritage has been attributed to APOL1 genetic variation. We determined the frequency of the APOL1 G1 and G2 risk variants together with the prevalence of HIV-associated nephropathy (HIVAN) among individuals of Ethiopian ancestry to determine whether the kidney disease genetic risk is PanAfrican or restricted to West Africa, and can explain the previously reported low risk of HIVAN among Ethiopians.
  
  
  METHODS
  We studied a cohort of 338 HIV-infected individuals of Ethiopian ancestry treated in one Israeli and one Ethiopian center. We sought clinical evidence for HIVAN (serum creatinine >1.4 mg/dl or proteinuria >30 mg/dl in a spot urine sample). Genetic analyses included the genotyping of the APOL1 G1 and G2 variants, and a panel of 33 genomic ancestry-informative markers. Statistical analysis compared clinical and genetic indices for HIV-infected individuals of Ethiopian ancestry and overall Ethiopians to those reported for HIV-infected African-Americans, overall African-Americans, West Africans and non-Africans.
  
  
  RESULTS
  Three (0.8%) of 338 HIV-infected patients of Ethiopian ancestry showed clinical criteria compatible with renal impairment. Two of these 3 patients also have severe poorly controlled diabetes mellitus. The third nondiabetic patient underwent renal biopsy which ruled out HIVAN. This absence of clinically apparent HIVAN was significantly different from that reported for African-Americans. The APOL1 G1 and G2 risk variants were found, respectively, in 0 and 2 (heterozygote state) of the 338 HIV-infected individuals. Global ancestry and the frequencies of the APOL1 G1 and G2 variants are not statistically different from their frequencies in the general Ethiopian population, but are significantly and dramatically lower than those observed among HIV-infected African-Americans, African-Americans and West Africans.
  
  
  CONCLUSIONS
  The coinciding absence of HIVAN and the APOL1 risk variants among HIV-infected individuals of Ethiopian ancestry support a Western rather than Pan-African ancestry risk for ESKD, and can readily explain the lack of HIVAN among individuals of Ethiopian ancestry.
authors.affiliation: Molecular Medicine Laboratory, Rambam Health Care Campus, Haifa, Israel.
authors.forename: Doron M
authors.initials: DM
authors.lastname: Behar
authors.forename: Eynat
authors.initials: E
authors.lastname: Kedem
authors.forename: Saharon
authors.initials: S
authors.lastname: Rosset
authors.forename: Yonas
authors.initials: Y
authors.lastname: Haileselassie
authors.forename: Shay
authors.initials: S
authors.lastname: Tzur
authors.forename: Zipi
authors.initials: Z
authors.lastname: Kra-Oz
authors.forename: Walter G
authors.initials: WG
authors.lastname: Wasser
authors.forename: Yotam
authors.initials: Y
authors.lastname: Shenhar
authors.forename: Eduardo
authors.initials: E
authors.lastname: Shahar
authors.forename: Gamal
authors.initials: G
authors.lastname: Hassoun
authors.forename: Carcom
authors.initials: C
authors.lastname: Maor
authors.forename: Dawit
authors.initials: D
authors.lastname: Wolday
authors.forename: Shimon
authors.initials: S
authors.lastname: Pollack
authors.forename: Karl
authors.initials: K
authors.lastname: Skorecki
mesh_terms: D016263:AIDS-Associated Nephropathy / Q000453:epidemiology / Q000235:genetics*; D000328:Adult; D000075944:Apolipoprotein L1; D001053:Apolipoproteins / Q000235:genetics*; D005002:Ethiopia / Q000453:epidemiology; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008075:Lipoproteins, HDL / Q000235:genetics*; D008297:Male; D012307:Risk Factors
chemical_list: C108666:APOL1 protein, human; D000075944:Apolipoprotein L1; D001053:Apolipoproteins; D008075:Lipoproteins, HDL