[custom_adv] Achondroplasia is a genetic disorder that results in dwarfism. [custom_adv] In those with the condition, the arms and legs are short, while the torso is typically of normal length. [custom_adv] Those affected have an average adult height of 131 centimetres (4 ft 4 in) for males and 123 centimetres (4 ft) for females. Other features include an enlarged head and prominent forehead. It does not affect intelligence. [custom_adv] Achondroplasia is due to a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. [custom_adv] In about 80% of cases, this occurs as a new mutation during early development. In the other cases, it is inherited from one's parents in an autosomal dominant manner. Those with two affected genes do not typically survive. [custom_adv] Treatments may include support groups and growth hormone therapy. Efforts to treat or prevent complications such as obesity, hydrocephalus, obstructive sleep apnea, middle ear infections or spinal stenosis may be required.