title: Prevalence of partial deficiency of red cell triosephosphate isomerase in Germany--a study of 3000 people.
abstract: During a heterozygote screening of nearly 3000 persons, triosephosphate isomerase (TPI) deficiencies in erythrocytes were discovered in 11 unrelated persons, showing a residual activity between 39 and 76% of normal activity. Extensive genealogic studies were performed to confirm that these persons with TPI deficiency were heterozygous carriers. The total heterozygote frequency of triosephosphate isomerase deficiencies was 3.7/1000. The persons with heterozygous deficiency could be divided into two categories. Subjects of category I had a mean residual activity of 49% of the expected normal activity and were represented by a frequency of 1.3/1000. Subjects of category II had a mean residual activity of 67% of the expected normal activity and were represented by a frequency of 2.4/1000. None of the heterozygous persons showed an electrophoretic variant. The immunologic specific activity was normal with one exception. Therefore, we assume that in many cases of our heterozygous TPI-deficiencies a TPI protein with a normal specific activity is synthesized to a diminished degree.
mesh_terms: D002238:Carbohydrate Epimerases / Q000235:genetics*; D004912:Erythrocytes / Q000201:enzymology*; D005787:Gene Frequency; D005858:Germany; D006579:Heterozygote; D006801:Humans; D007158:Immunologic Techniques; D007527:Isoenzymes / Q000235:genetics; D010375:Pedigree; D014305:Triose-Phosphate Isomerase / Q000097:blood / Q000172:deficiency / Q000235:genetics*
chemical_list: D007527:Isoenzymes; D002238:Carbohydrate Epimerases; D014305:Triose-Phosphate Isomerase