Aplasia (; from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''a'', "not", "no" + ''plasis'', "formation") is a

birth defect A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities c ...

where an organ or tissue is wholly or largely absent. It is caused by a defect in a developmental process.

Aplastic anemia Aplastic anemia is a cancer in which the body fails to make blood cells in sufficient numbers. Blood cells are produced in the bone marrow by stem cells that reside there. Aplastic anemia causes a deficiency of all blood cell types: red blood ...

is the failure of the body to produce blood cells. It may occur at any time, and has multiple causes. __TOC__

Examples

* Acquired pure red cell aplasia * Aplasia cutis congenita *

* Germ cell aplasia, also known as Sertoli cell-only syndrome * Radial aplasia *

Thymic The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or ''T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. ...

aplasia, which is found in

DiGeorge syndrome DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent ...

and also occurs naturally as part of the gradual loss of function of the

immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as Tumor immunology, cancer cells and objects such ...

later in life

References

Medical terminology Anatomy Embryology Blood disorders {{congenital-malformation-stub

Examples

See also

References