Separation of Normoblasts from Whole Blood by Ultracentrifugation on Arabino‐Galactane Discontinuous Gradients: A Tool for Prenatal Diagnosis

: Normoblasts can be separated at high resolution from whole blood by ultracentrifugation on discontinuous gradients of arabino-galactane after the red blood cells are removed by sedimentation. With this method, isolation of fetal normoblasts from maternal blood could provide a tool for rapid prenatal diagnosis. The availability of this noninvasive technique could avoid the cost and the risks of miscarriage that are associated with the current invasive procedures.