Why do a bone marrow biopsy?

What are some of the promising clinical trials going on now for myelodysplastic syndromes?
How do you distinguish between a diagnosis of myelodysplastic syndromes and acute myeloid leukemia?
If a patient is being observed what does observation look like?
What is a transfusion and how often would a patient get one?
When might a transplant be considered in myelodysplastic syndromes?
What are the treatments for low risk and high risk myelodysplastic syndromes?