Alkalinephosphatase activity in leukocytes of patients with trisomy G-normal mosaicism.

Abstract

Chromosomal analyses of cultured leukocytes and fibroblasts of patients with trisomy G/normal mosaicism were done. Alkaline phosphatase (Kaplow) scores were determined for the leukocytes of these patients, a group of patients with Down's syndrome, and a group of controls. The scores of each person varied considerably at different times. The trisomy G mosaic group and the Down's syndrome group both had significantly higher mean scores than the controls. Contrary to expectations on the basis of a direct gene-enzyme relationship, the mean score of the trisomy G mosaic group was higher, though not significantly, than that of the group with Down's syndrome. To exclude possible errors due to the fact that the Kaplow method is semiquantitative, the scores were compared wih the activity values obtained with a biochemical method. There was good correlation between the results of the two methods.