My dad has low risk MDS. Only anemia, but transfusion dependent of theee units every 6 wks. Platelets and WBC are ok. Blasts in B.marrow1%. Prognosis?

Unpredictable. Don't try to second-guess. It's all percentage odds. He would do well to plan a normal life expectancy, but be prepared (as any person should be) for the onset of serious illness.