Stem cell research focuses on stem cells, which have a capacity to regenerate. A stem cell is capable of developing into other types of cells, like kidney cells, liver cells, heart cells, etc. These circulate and function to replace dysfunctional cells, naturally maintaining optimal health. Current medical research is focused on two particular types of stem cells -- adult and embryonic. Out of the three types, two are able to develop into any type of cell within the human body. These two are called totipotent and pluripotent, respectively.
Stem cell research provides great potential for discovering treatments and cures to a plethora of diseases including Parkinson's disease, schizophrenia, Alzheimer's disease, cancer, spinal cord injuries, and diabetes.
Limbs and organs could be grown in a lab from stem cells and then used in transplants or to help treat illnesses.
Scientists and doctors will be able to test millions of potential drugs and medicine, without the use of animals or human testers. This necessitates a process of simulating the effect the drug has on a specific population of cells. This would tell if the drug is useful, or has any problems.
An advantage of the usage of adult stem cells to treat disease is that a patient's own cells could be used to treat a patient. Risks would be quite reduced because patients' bodies would not reject their own cells.
Like any other new technology, it is also completely unknown what the long-term effects of such an interference with nature could materialize.
Embryonic stem cells may not be the solution for all ailments.
A disadvantage is that they are prespecialized; for instance, blood stem cells make only blood, and brain stem cells make only brain cells.
These are derived from embryos that are not a patient's own and the patient's body may reject them.