In experimental models of stroke, when given soon after infarct, G-CSF improves recovery.[11, 12] In clinical stroke, G-CSF when given in similar doses as used in haematology, was effective at mobilising CD34+ stem cells[13] and a number of trials have since been completed in acute[14, 15] and sub acute stroke.[16] In the largest study,[15] G-CSF showed no evidence of efficacy in 328 patients with hyperacute stroke. The gene discussed is CD34; the disease is Stroke.