Causes of Ankle Pain. 1  Ankylosing Spondylitis Ankylosing spondylitis is a type of arthritis that causes chronic inflammation of the spine. 2  Arthritis Arthritis is inflammation of one or more joints. 3  Broken Bone (Types of Bone Fractures) A broken bone is a fracture.
Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and weak muscle tone (hypotonia) in infancy. All affected individuals experience cognitive delays, but the intellectual disability is usually mild to moderate.
Down syndrome (or Down's syndrome) is a chromosomal disorder caused by an error in cell division that results in an extra 21st chromosome.his is caused by an error in cell division called nondisjunction, which leaves a sperm or egg cell with an extra copy of chromosome 21 before or at conception. Trisomy 21 accounts for 95% of Down syndrome cases, with 88% originating from nondisjunction of the mother's egg cell.