Decreased superoxide dismutase-2 activity in a patient with ring chromosome 6

Abstract
Manganese superoxide dismutase (SOD‐2) activity was measured in erythrocytes and leukocytes of a patient with ring chromosome 6. Compared to normal control individuals, SOD‐2 activity in leukocytes of the patient was lower, whereas cuprozinc SOD (SOD‐1) activity was normal. These findings suggest the cause of decreased enzyme activity is the effect of the ring form on production of the enzyme or inherent instability of ring chromosomes.