What Causes Dwarfism?
There are many causes of dwarfism. In fact, more than 200 conditions are known to cause short stature. However, one medical condition, achondroplasia, accounts for the majority of the cases of dwarfism.
Achondroplasia is the most common type of short-limbed dwarfism. Typical features of people with achondroplasia includes: average-size trunk, short arms and legs with particularly short upper arms and thighs, limited range of motion at the elbows, and an enlarged head (macrocephaly). The condition occurs in 1 in 15,000 to 40,000 newborns.
Genetic abnormalities (mutations) on a gene known as FGFR3 are the underlying cause of achondroplasia. The FGFR3 gene codes for a specific protein involved in the development and maintenance of bone and brain tissue. This protein limits the formation of bones from cartilage, interfering with skeletal development and bone growth.
Another important cause of dwarfism is the deficiency of a hormone known as Growth Hormone (GH) (somatotropin). In this case, insufficient amounts of GH may cause children to grow slowly or even indefinitely. There is no single cause for GH deficiency. It may be caused by a genetic disorder or damage to the pituitary gland. Even poor nutrition can cause GH deficiency.