This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Achondroplasia is a disorder of bone growth that prevents the changing of cartilage (particularly in the long bones of the arms and legs) to bone. It is characterized by dwarfism, limited range of motion at the elbows, large head size (macrocephaly), small fingers, and normal intelligence. Achondroplasia can cause health complications such as interruption of breathing (apnea), obesity, recurrent ear infections, an exaggerated inward curve of the lumbar spine (lordosis). More serious problems include a narrowing of the spinal canal that can pinch (compress) the upper part of the spinal cord (spinal stenosis) and a buildup of fluid in the brain (hydrocephalus). Some people with achondroplasia may have delayed motor development early on, but cognition is normal. Achondroplasia is caused by mutations in the FGFR3 gene. Inheritance is autosomal dominant. Treatment may include medication with growth hormone, and surgery aimed to correct the spine, or bone problems, as well, as to reduce the pressure inside the brain in cases of hydrocephaly. Prognosis with achondroplasia is good except in cases of spinal compression at the neck.
For more information, visit GARD.