1 Adult stem cells : The Bone marrow is an abundant source of stem cells. Since they are derived from patient's own body There is no problem of "REJECTION" . Also there are no ethical Issues for Doctors in using these cells. The Maximum Clinical Data are now available with Adult stem cells.

2. Umbilical cord stem cells: The Newborn child's Cord blood is a rich source of Stem cells. They have great potential for future applications in medicine. But the present treatment status of these cells are not clear.

3. Embryonic stem cells: The Embryo in the first 10 weeks is the richest source of Undifferentiated Stem cells which can potentially change to virtually any organ. Apart from Ethical concerns about Destruction.