The present report provides evidence that hydroxyurea (HU) improves th
e beta thalassaemic phenotype in mice receiving 200 mg/kg/d for 30 d.
The haematocrit rose from 29 +/- 3% at day 0 to 37 +/- 4% at day 30 (P
<0.05), despite myelosuppression and decreased reticulocyte counts. Th
e beta minor/alpha ratio of globin chain synthesis increased from 0.78
at day 0 to 0.97 at day 30 (P<0.001). Membrane defects improved: the
proportion of bound alpha chains decreased, the proportion of spectrin
and ankyrin increased and red cell deformability also increased.