Stem cells can be used to treat human disorders

Since stem cells can divide into a range of specialised cell types, doctors and scientists think they could be used to replace cells damaged by illness or injury.

Some stem cell therapies already exist

Some stem cell therapies already exist for some diseases affecting the blood and immune system.
Bone marrow contains stem cells that can become specialised to form any type of blood cell. Bone marrow transplants can be used to replace the faulty bone marrow in patients that produce abnormal blood cells. The stem cells in the transplanted bone marrow divide to produce healthy blood cells.
This technique has been used to successfully treat leukaemia and lymphoma.
It has also been used to treat some genetic disorders, such as sickle-cell anaemia and severe combined immunodeficiency (SCID):

EXAMPLE
Severe combined immunodeficiency (SCID) is a genetic disorder that affects the immune system. People with SCID have a poorly functioning immune system as their white blood cells are defective.
This means that they can't defend the body against infections by identifying and destroying microorganisms. So SCID sufferers are extremely susceptible to infections. Treatment with a bone marrow transplant replaces the faulty bone marrow with donor bone marrow that contains stem cells without the faulty genes that cause SCID.
These then differentiate to produce functional white blood cells. These cells can identify and destroy invading pathogens, so the immune system functions properly.

Stem cells could be used to treat other diseases

Scientists are researching the use of stem cells as treatment for lots of conditions, including:

Spinal cord injuries - replace damaged nerve tissue
Heart disease and damage caused by heart attacks - replace damaged heart tissue
Bladder conditions - grow whole new bladders which can then be implanted.
Respiratory diseases - donated windpipes cna be striped down and then covered with tissue generated by stem cells.
Organ transplants - organs could be grown from stem cells for people on the organ donor waiting list.

	Created by Lucy Nove over 7 years ago

A2 Biology (Mutations and Gene Expression) Note on Stem Cells, created by Lucy Nove on 29/01/2017.