Novel splice site and nonsense variants in INVS cause infantile nephronophthisis

Nephronophthisis is an autosomal recessive disease characterized by cystic kidney disease with progression to end-stage kidney disease in children and adolescents with or without extra-renal involvement. It is caused by biallelic pathogenic variants in 19 genes including INVS that encodes a ciliary protein essential for renal development and left-right axis establishment. We report a child with bilateral enlarged, echogenic, polycystic kidneys with end-stage renal disease, anemia and metabolic acidosis caused by biallelic novel pathogenic variants, c.796 + 5G > A and c.1789C > T in INVS. We show that the variant, c.796 + 5G > A disrupts the canonical splicing and nonsense variant, c.1789C > T results in nonsense mediated decay.