Studies in sickle-cell anemia. V. Sickle-cell hemoglobin C disease; report of two cases in siblings with clinical and genetic observations and a brief review of the literature.

Abstract

INTRODUCTION Within the past few years, the application of newer knowledge, chiefly involving genetic, biochemical, and electrophoretic techniques, has resulted in the recognition of previously unknown intrinsic properties of human hemoglobin. The application of these newer tools to the study of sickle-cell anemia has revealed that the condition is not a simple disease entity but is in reality a hemolytic syndrome which may be separated into specific subtypes depending upon the variety of abnormal hemoglobin present. To date, the hemoglobins which have been identified by chemical and/or electrophoretic studies are as follows *: A—Normal adult hemoglobin F—Fetal hemoglobin S—Sickle-cell hemoglobin C—C hemoglobin D—D hemoglobin E—E hemoglobin G—G hemoglobin† The pathologic effects of various known combinations of abnormal hemoglobins are listed in Table 1. The current designation of sickle-cell anemia is reserved for the type in which the genes responsible for sickling are homozygous. Statistically, this is the commonest variety. The second