Due to an autosomal dominant mutation in fibroblast growth factor receptor 3 (FGFR3) [3], people with achondroplasia have disproportional short stature; short arms with a limited range of motion, short thighs, an enlarged head, leg bowing, and hypermobile joints (hips, knees, shoulders), with the exception of the elbows, which are stiff and have a limited range of motion [2]. The gene discussed is FGFR3; the disease is achondroplasia.