What is "saddan"

SADDAN (severe achondroplasia with developmental delay and acanthosis nigricans) is a rare inherited disorder of bone growth characterized by skeletal, brain, and skin abnormalities.

All people with this condition are extremely short with particularly short arms and legs. Other signs and symptoms include unusual bowing of the leg bones; a small chest with short ribs and curved collar bones; short, broad fingers; and folds of extra skin on the arms and legs. Structural abnormalities of the brain lead to seizures, profound developmental delay, and mental retardation. Acanthosis nigricans, a progressive skin disorder characterized by thick, dark, velvety skin, develops in infancy or early childhood. People with SADDAN often live into childhood and adulthood.

Many of the features of SADDAN are similar to those seen in other skeletal disorders, specifically achondroplasia and thanatophoric dysplasia.