question: What is Achondroplasia?: 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, small fingers, and normal intelligence. Achondroplasia can cause health complications such as apnea, obesity, recurrent ear infections, and lordosis of the spine. Achondroplasia is caused by mutations in the FGFR3 gene. It is inherited in an autosomal dominant fashion.