What is the potential use of human stem cells?

In medicine, stem cell transplants can be carried out to replace cells damaged by disease or chemotherapy. This is done by producing cells in a lab setting. Stem cells can also be used for researching the reason for genetic defects in cells. They also help to research the reason for why diseases happen or why specific cells become cancerous. Researchers do this by observing stem cells mature into cells in bones, nerves, heart muscles, and other tissue. Another use of stem cells is that they may help test drugs for their efficacy and safety. Human stem cells would be produced into tissue-specific cells to test the safety of novel drugs. As an example, nerve cells could be produced to test a new drug for nerve diseases. The goal of the test would be to determine if the novel drug had any harmful or beneficial effects on the cells.