Alteration in the polysomal distribution of γ-globin mRNA in reticulocytes subsequent to butyrate therapy. Before therapy (♦) and at 24 hours (▪). Fractions 1 and 2 are the prepolysomal region; fractions 5 to 8, the 1 to 3 ribosomal region. (A) Analysis of γ-globin mRNA from reticulocytes from a representative patient with SCD responsive to butyrate. (B) Analysis of γ-globin mRNA from reticulocytes from another representative patient with SCD responsive to butyrate.