A 40- to 70-fold increase in erythrocyte adenosine deaminase (ADA) activity has been associated with chronic hemolytic anemia and decreased erythrocyte ATP levels. This disorder is present in 11 of 23 members of an affected kindred, is inherited as an autosomal dominant trait, and is unusual in that the overactivity of ADA is confined to erythrocytes. The kinetic and physiochemical properties of the ADA enzyme in red cells are normal, suggesting the cell-line specific overabundance of a normal enzyme. Since this enzyme is completely stable over the 120 day lifespan of the erythrocyte, this disorder appears to represent a state of true enzyme overproduction rather than of increased enzyme stability. We propose to further define the molecular defect in that kindred by 1) defining the levels of ADA-specific mRNA in erythroid and non-erythroid cells; 2) quantitating the amount of ADA protein in red cells and lymphoblasts from affected individuals; 3) examining DNA from cultured lymphoblasts for altered patterns of restriction endonuclease digestion; 4) constructing a cDNA library from reticulocyte poly A+-selected RNA and cloning the two ADA alleles from this library; 5) sequencing full length ADA clones looking for specific nucleotide insertions, deletions, or substitutions; 6) examining the in vitro translation potential of ADA mRNA obtained from affected reticulocytes or from RNA copies of abnormal cDNA clones; 7) examing the tissue specificity of ADA expression by quantitating the production of ADA enzyme in erythroid and non-erythroid cell lines transfected with ADA cDNAs cloned into a selectable expression vector. These experiments should elucidate a mechanism for the selective overproduction of a specific protein mulecule in a single human cell type. The results of these studies should have important ramifications for the basic understanding of tissue-specific gene expression, as well as for the use of gene transfer techniques in the treatment of congenital enzyme deficiency states.

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
Project #
Application #
Study Section
Hematology Subcommittee 2 (HEM)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Michigan Ann Arbor
Schools of Medicine
Ann Arbor
United States
Zip Code
Chen, E H; Mitchell, B S (1994) Hereditary overexpression of adenosine deaminase in erythrocytes: studies in erythroid cell lines and transgenic mice. Blood 84:2346-53
Chen, E H; Tartaglia, A P; Mitchell, B S (1993) Hereditary overexpression of adenosine deaminase in erythrocytes: evidence for a cis-acting mutation. Am J Hum Genet 53:889-93
Chottiner, E G; Ginsburg, D; Tartaglia, A P et al. (1989) Erythrocyte adenosine deaminase overproduction in hereditary hemolytic anemia. Blood 74:448-53
Gribbin, T; Chottiner, E; Ginsburg, D et al. (1989) Identification of an Apa I polymorphism within the human adenosine deaminase (ADA) gene. Nucleic Acids Res 17:3626
Gan, T E; Dadonna, P E; Mitchell, B S (1987) Genetic expression of adenosine deaminase in human lymphoid malignancies. Blood 69:1376-80
Chottiner, E G; Cloft, H J; Tartaglia, A P et al. (1987) Elevated adenosine deaminase activity and hereditary hemolytic anemia. Evidence for abnormal translational control of protein synthesis. J Clin Invest 79:1001-5