Laboratory for Molecular Diagnostics
Center for Nephrology and Metabolic Disorders

Carbonic anhydrase 2

Carbonic anhydrase 2 is an enzyme found predominantly in the lumen of renal tubules where it plays an essential role in proton secretion. If defective, mixed type renal tubular acidosis results. The enzyme has an additional function in bone turnover where a defect causes osteopetrosis.


Carbonic anhydrase 2 is predominantly found in kidney and bone.


If the function of this enzyme is deficient renal excretion of protons is impaired. Because the enzyme is essential in proximal and distal tubules a mixed type renal tubular acidosis results. The characteristic bone symptom is osteopetrosis.

Gene Regulation

In kidney, it acts intraluminal in both proximal and distal tubules, where it facilitates proton secretion and bicarbonate reabsorption. In bone turnover the enzyme is involved in bone mineral resorption.

Test Strategy

Carbonic anhydrase activity can be measured, but the method appears clumsy nowadays.[Error: Macro 'ref' doesn't exist]


Interpretation of negativ mutational analysis should take into account the possibility of phenocopy caused by concurrent mutations of TCIRG1 and ATP6V1B1 genes.[Error: Macro 'ref' doesn't exist]


Clinic Method Carrier testing
Turnaround 5 days
Specimen type genomic DNA
Clinic Method Massive parallel sequencing
Turnaround 25 days
Specimen type genomic DNA
Clinic Method Genomic sequencing of the entire coding region
Turnaround 20 days
Specimen type genomic DNA

Related Diseases:

Combined renal tubular acidosis 3 with osteopetrosis 3



Borthwick KJ et al. (2003) A phenocopy of CAII deficiency: a novel genetic explanation for inherited infantile osteopetrosis with distal renal tubular acidosis.


Lotan D et al. (2006) Clinical and molecular findings in a family with the carbonic anhydrase II deficiency syndrome.


None (1960) A simplified micromethod for the determination of carbonic anhydrase and its inhibitors.


Orphanet article

Orphanet ID 119117 [^]

NCBI article

NCBI 760 [^]

OMIM.ORG article

Omim 611492 [^]

Wikipedia article

Wikipedia EN (Carbonic_anhydrase_II) [^]
Update: April 29, 2019