Adenosine deaminase polymorphism in man

Abstract

Summary A new and specific method for the study of adenosine deaminase isozymes is described. Examination of red‐cell lysates has revealed three genetically determined electrophoretically different ADA phenotypes: ADA 1, ADA 2–1 and ADA 2. Family studies indicate that these phenotypes are determined by two alleles, ADA 1 and ADA 2 at an autosomal locus. Preliminary population data suggest that ADA 2 has a frequency of about 0.06 in European, 0.04 in Negroes and 0.11 in Asiatic Indians. The behaviour of the ADA isozyme pattern on storage or after treatment with thiol reagents suggests the occurrence of reactive sulphydryl groups in the enzyme molecules.