Table 1.

Genetics of primary renal tubular acidosis (RTA)a

SyndromeGene LocalizationLocus SymbolGene Product
a NBC-1, Na+-HCO3 cotransporter; NHE-3, Na+-H+ exchanger; AE1, Cl-HCO3 exchanger; ENaC, epithelial Na+ channel; MC, mineralocorticoid receptor.
Primary proximal RTA (type 2)
    autosomal dominant???
    autosomal recessive with ocular abnormalities4q21SLC4A4NBC-1
    sporadic in infancyImmaturity of NHE-3 ?
Primary distal RTA (type 1)
    autosomal dominant17q21–22SLC4A1AE1
    autosomal recessive with deafness (rdRTA1)2p13ATP6B1B1 subunit of H+ ATP-ase
    autosomal recessive without deafness (rdRTA2)7q33–34ATP6N1B116-kD subunit of H+ ATP-ase
Combined proximal and distal RTA (type 3)
    autosomal recessive with osteopetrosis8q22CA2CA II
Hyperkalemic distal RTA (type 4)
    pseudohypoaldosteronism type 1
        autosomal dominant renal form4q31.1MLRMineralocorticoid receptor
        autosomal recessive multiple-organ form16p12SNCC1B, SCNN1Gβ and γ ENaC
12p13SNCC1Aα ENaC
        “early-childhood” hyperkalemiaImmaturity of MC receptor?
    pseudohypoaldosteronism type 2 (Gordon syndrome)12p13.3WNK1WNK1 kinase
17p11-q21WNK4WNK4 kinase