Anemia, Hemolytic, Cold Antibody is a type of autoimmune hemolytic anemia, which is a condition in which the body's immune system mistakenly attacks and destroys its own red blood cells. This type of anemia is caused by the production of antibodie...

Anemia, Hereditary Nonspherocytic Hemolytic (HNSH) is a type of anemia caused by a genetic defect that affects the body’s ability to produce healthy red blood cells. In this condition, red blood cells are destroyed faster than they can be replac...

Anemia, megaloblastic is a type of anemia caused by a deficiency of vitamin B12 or folate. It is characterized by the presence of large, immature red blood cells in the bloodstream. Symptoms of anemia, megaloblastic include fatigue, weakness, pale...

Anemia, Pernicious is a type of anemia caused by a lack of vitamin B12. It is caused by an inability to absorb vitamin B12 due to a lack of intrinsic factor, a protein produced in the stomach. Symptoms of Pernicious Anemia include fatigue, weaknes...

Anemias, Sideroblastic is a type of anemia caused by a defect in the production of hemoglobin, the protein in red blood cells that carries oxygen. This type of anemia is caused by a problem with the body's ability to absorb iron, which is necessar...

Anencephaly facts Anencephaly is an example of a neural tube defect, a condition that results from an error in the first weeks of embryonic development. In anencephaly, the bones of the skull and brain do not develop prope...

Anencephaly is a rare birth defect in which a baby is born without parts of the brain and skull. It is a fatal condition and most babies with anencephaly die shortly after birth....

An aneurysm is an abnormal area of localized widening of a blood vessel. The aorta bulges at the site of an aneurysm like a weak spot on a worn tire. Aortic aneurysms are typically spindle-shaped and involve the aorta belo...

An aneurysm of the sinus of Valsalva is a bulge or ballooning of the wall of one of the three sinuses of Valsalva, which are located in the heart. It is a rare condition that can cause serious complications, including aortic regurgitation, aortic ...

Aneurysm-osteoarthritis syndrome is a rare genetic disorder characterized by aneurysms (weakened and bulging blood vessels) in the brain and/or spinal cord, as well as osteoarthritis (degenerative joint disease). It is caused by a mutation in the ...

An aneurysmal bone cyst (ABC) is a rare, benign, expansile lesion of the bone that is characterized by a cystic cavity filled with blood. It is most commonly found in the long bones of the body, such as the femur, tibia, and humerus, but can also ...

Angel-shaped phalango-epiphyseal dysplasia (APED) is a rare genetic disorder that affects the growth of bones in the hands and feet. It is characterized by short stature, short fingers and toes, and a distinctive angel-shaped appearance of the epi...

Angelman Syndrome is a rare genetic disorder that affects the nervous system. It is characterized by severe developmental delays, intellectual disability, speech impairment, and movement and balance disorders. People with Angelman Syndrome often h...

Angelman syndrome is caused by a point mutation in the UBE3A gene, which is located on chromosome 15. This mutation results in the loss of function of the gene, which is responsible for the production of a protein called ubiquitin-protein ligase E...

Angelman syndrome is a genetic disorder caused by a defect in the imprinting process of the 15q11-q13 region of the genome. This region contains several genes that are important for normal brain development. When the imprinting process is disrupte...

Angelman syndrome is a genetic disorder caused by a deletion of a small piece of chromosome 15 in the region known as 15q11-q13. This deletion is usually inherited from the mother. The deletion results in the loss of several genes, which can lead ...

Angelman syndrome is a genetic disorder caused by a deletion of a small piece of chromosome 15, or by a mutation in the UBE3A gene located on the same chromosome. It is also caused by paternal uniparental disomy of chromosome 15, which is when bot...