The role of carbonic anhydrase in autosomal dominant osteopetrosis

Twenty-eight patients with two different radiological types of the autosomal dominant form of osteopetrosis, from six different kindreds, were investigated and compared with age- and sex-matched controls, in order to evaluate the role of carbonic anhydrase in this disorder. There were 15 patients with Type I and 13 with type II osteopetrosis. The concentrations of haemoglobin and bicarbonate were normal in both types and without differences between the types. The concentration of carbonic anhydrase isoenzyme II (CA II) in the erythrocytes did not differ from controls in any of the two types. It is concluded that CA II does not seem to play any pathogenetic role in these two different forms of autosomal dominant osteopetrosis.