Hemoglobin Switching in Sheep and Goats: Occurrence of Hemoglobins A and C in the Same Red Cell

Abstract

Sheep and goats switch from the synthesis of hemoglobin A (α₂β₂^A) to hemoglobin C (α₂β₂^C) when made anemic. We have demonstrated the existence of the asymmetrical hybrid hemoglobin, α₂β^Aβ^C, in the circulating red cells of anemic sheep. These erythroid cells, therefore, synthesized both A and C hemoglobin simultaneously. Thus, the switch appears to be mediated by selective gene expression rather than by a clonal or cellular selective mechanism.