GPI Mount Scopus--a variant of glucosephosphate isomerase deficiency.

Glucosephosphate isomerase (GPI) deficiency is an unusual cause of hereditary nonspherocytic hemolytic anemia. The disease, inherited as an autosomal recessive disorder, is most often manifested by symptoms and signs of chronic hemolysis, ameliorated by splenectomy. We recently diagnosed GPI deficiency in a 23-year-old Ashkenazi Jewish man who displayed the typical clinical course of this disorder. The biophysical characteristics of the GPI variant are slow electrophoretic mobility, presence of only one of the two bands normally present, and extreme thermolability. To the best of our knowledge, this is the first report of GPI deficiency in a patient of Jewish descent, and we propose to designate this enzyme variant "GPI Mount Scopus".