"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 (macrocephaly), small fingers, and normal intelligence. Achondroplasia can cause health complications such as interruption of breathing (apnea), obesity, recurrent ear infections.

Cause?
Achondroplasia is caused by mutations in the FGFR3 gene.This gene provides instructions for making a protein that is involved in the development and maintenance of bone and brain tissue.

Symptoms?

a short stature that’s significantly below average for age and sex

short arms and legs, especially the upper arms and thighs, in comparison to body height

short fingers in which the ring and middle fingers may also point away from each other

a disproportionately large head compared to the body

an abnormally large, prominent forehead

an underdeveloped area of the face between the forehead and upper jaw.