The prevalence of APOL1 gene variants in a cohort of renal disease patients in Western Saudi Arabia

Two variants for APOL1; the gastrointestinal (G1) variant (S342G and 1384M substitutions) and the G2 variant (N388 and Y389 deletions) have been previously described to be associated with renal disease. The prevalence of APOL1 variants in Saudi Arabia is unknown. We aimed to determine the prevalence of APOL1 variants in a cohort of patients with renal disease in Saudi Arabia. Patients with renal disease followed up at King Abdulaziz University Hospital were approached consecutively at the out patient clinic, and unaffected controls were approached at the blood donation area. Clinical and laboratory data were collected from electronic medical records. Laboratory variables in controls were obtained on enrollment. This is a cross-sectional, cohort study. One hundred and one patients with a mean age of 54.5 (±19) years, and 119 unaffected controls with a mean age of 31.9 (±7.89) years, were enrolled. Seventy-four patients (68.5%) had hypertension and 62 (57.4%) had diabetes. The mean estimated glomerular filtration rate was 22.47 (± 27.6) mL/min. Two patients were heterozygous for G1 allele. Among the control group, two were heterozygous for G1 allele, and three were heterozygous for G2. All five controls had no evidence of renal disease and no family history of renal disease. The prevalence of APOL1 genetic risk variants in the study cohort was very low. Larger studies are needed to determine the prevalence among renal disease patients in Saudi Arabia.