The first step in the search for a donor is to have a blood test to identify your tissue type. Each cell in the body has a combination of a group of proteins (HLA) on its surface.

Once your tissue type is known, other people can have a blood test done to see if their type of tissue is the same as yours. This is known as HLA matching. Having an exact match increases the chances of the transplant being a success.

It is likely for there to be match between you and your brothers or sisters. If there is no match found among your relatives, your doctors will search for an unrelated volunteer donor. Another source of stem cells is blood from the umbilical cord. This is stored in blood banks.

Potential donors will have tests done before donating their cells. Stem cells can be collected form the donor's blood or bone marrow.