the long and the short of it
A Brief Summery
Famous People with Dwarfism
Disease Symptoms and Biology of Disease
Dwarfism disorder typically causes people to be disproportionately short (adults around 4 feet). In many cases the person has an average-size trunk and very short limbs. There are variations where people have a very short trunk and disproportionately large limbs). In these cases, the heads are typically large compared to the body. Most people with disproportionate dwarfism are intellectually normal.
The following are common features:
- Average adult height around 4 feet
- Average-size trunk
- Short arms and legs. Short upper arms and legs
- Disproportionately large head. Prominent forehead. Flattened bridge of the nose
- Short fingers. A wide separation between the middle and ring fingers
- Limited elbow mobility
- Bowed legs
- Swayed lower back
Over 99% of cases of achondroplasia (short-limbed dwarfism) is caused by two mutations in the FGFR3 gene. Both of these mutations cause an amino acid (protein building block) glycine to be replaced with arginine at protein postion 380. It is written as Gly380Arg or G380R. It is generally believed that it is causes the receptors to be overly active. This leads to bone growth disturbances.
Diagnosis/Treatment/and Ethical Implications
There are many indicators that hint towards dwarfism. These include:
Measurement – Doctors typically measure height, weight and head circumference as part of
well-baby visits. If these values are trending beyond typical percentile rankings, it can be a
Appearance – Pediatricians may identify distinctive facial and skeletal features that are common
Imaging technology –X-rays may be useful in identifying certain abnormalities. These
abnormalities of the skull and skeleton can help identify the disorder. MRIs may be used to
reveal pituitary gland or hypothalamus abnormalities. These can play a role with the hormone
Family History - Since it is genetic, a family history may be a good indicator.
Genetic Testing – There are currently genetic tests for many of the known dwarfism genes. In
most cases, these tests are not given, since dwarfism is easily identified using simpler tests.
Once diagnosed. Dwarfism can’t generally be cured. Unfortunately, dwarfism often comes with
numerous associated problems. Many treatments are done to reduce these problems. These include:
Relieving pressure on the brain by inserting shunts to drain excess fluid
Surgeries are often conducted to correct bone direction.
Expand small airways with a tracheotomy
Fix bowed legs, club foot, and cleft palates with corrective deformity surgeries
It is common to have tonsils that are disproportionate to small heads. This is often fixed by
removing tonsils and adenoids
Spinal cord compression is often fixed with surgery to widen the spinal canal.
Physical therapy is often used for strengthen muscles and increase range of motion.
Back braces are often used to help with curvature of the spine.
Draining tubes are often used to prevent hearing loss due to ear infections.
Small jaws often cause teeth crowding. This is fixed with orthodontics.
In people where dwarfism is caused by hormonal deficiencies, doctors may treat the patients
with synthetic hormones. This can include daily injections for years and is somewhat
Obesity is often avoided with special diet and exercise.
One of the more controversial surgeries that some people choose is extended limb lengthening. This is
a series of surgeries that can be done as a person with dwarfism grows. This surgery has multiple risks
and can be physically and emotionally draining. It is therefore recommended that it be delayed until the
person being operated on is old enough to decide to have the surgery.
Type of Mutation and Type of Inheritance
Achondroplasia dwarfism is an autosomal dominant pattern inherited trait. This means that a copy of the altered gene in each cell is enough to cause the disorder. As much as 80% of people with dwarfism have an average sized parent. In these cases, a new mutation in the FGFR3 gene is created. In the remaining 20%, the gene is inherited from one or both affected parents. When a person inherits altered genes from both parents, it is common to have a severe form of dwarfism that includes an underdeveloped rib cage and extremely shortened bones. Many of these individuals are stillborn or die shortly after birth of respiratory failure.
Children’s Health: Dwarfism. (2005). Retrieved from http://www.webmd.com/children/dwarfism-causes-treatments?page=3
Diseases and Conditions Dwarfism. (1998). Retrieved from http://www.mayoclinic.org/diseases-conditions/dwarfism/basics/definition/con-20032297
Dwarfism. (2016). Retrieved from http://www.healthofchildren.com/D/Dwarfism.html
Dwarfism: How is Primordial dwarfism Inherited? (n.d.). Retrieved from http://dwarfism.weebly.com/how-is-premordial-dwarfism-inherited.html
Genetics Home Reference: Dwarfism. (June 2013). Retrieved from https://ghr.nlm.nih.gov/gene/FGFR3
Genetics Home Reference Guide: Achondroplasia. (May 2012). Retrieved from https://ghr.nlm.nih.gov/condition/achondroplasia
Learning About Achondroplasia. (2012). Retrieved from https://www.genome.gov/19517823
SANGHAVI, D. M. (2006, December 5). Wanting Babies Like Themselves, Some Parents Choose Genetic Defects. The New York Times. Retrieved from http://www.nytimes.com/2006/12/05/health/05essa.html?_r=0