For patients and their families, embryonic stem cell research offers the hope of cures for chronic and debilitating conditions, such as juvenile diabetes, Alzheimer’s disease, Parkinson’s disease, spinal cord injuries and blindness. For scientists, it represents a revolutionary path to discovering the causes and cures for many more human maladies. Embryonic stem cells are pluripotent, that is, they have the unique ability to develop into any of the 220 cell types in the human body. In addition to their versatility, embryonic stem cells are easier to grow in the laboratory than adult stem cells.