“…The characteristic features of this condition would seem to be: (i) chronic unconjugated hyperbilirubina:mia with values for total serum bilirubin up to 7 mg. per 100 ml., (ii) normal results to tests of liver function, (iii) erythroid hyperplasia of the bone marrow, (iv) reticulocytosis in the peripheral blood, (v) increased plasma iron turnover, increased serum iron level and increased percentage saturation of the total iron binding capacity, (vi) increased fa:cal and urinary urobilinogen excretion, and (vii) normal peripheral red cell survival time. The degree of autoha:molysis, the red cell osmotic fragility and the levels of red cell enzymes are normal (Klaus, 1964), as are the red cell protoporphyrin and coproporphyrin concentrations (Berendsohn et alii, 1964). This is a rare disorder, which manifests itself usually in the second decade, affecting males and females equally, and in the cases reported by Israels et alii (1959) and Arias (1962a) it was familial.…”