Abstract:
In black African children with focal segmental glomerulosclerosis (FSGS) there are high rates
of steroid resistance. The aim was to determine genetic associations with apolipoprotein L1
(APOL1) renal risk variants and podocin (NPHS2) variants in 30 unrelated black South African
children with FSGS. Three APOL1 variants were genotyped and the exons of the NPHS2 gene
sequenced in the cases and controls. APOL1 risk alleles show a modest association with
steroid sensitive nephrotic syndrome (SSNS) and steroid resistant nephrotic syndrome
(SRNS). The NPHS2 V260E variant was present in SRNS cases (V/V = 5; V/E = 4; E/E = 11),
and was absent in SSNS cases. Haplotype analysis suggests a single mutation origin for
V260E and it was associated with a decline in kidney function over a 60-month period (p =
0.026). The V260E variant is a good predictor of autosomal recessive SRNS in black South
African children and could provide useful information in a clinical setting.