Achondroplasia- Dwarfism By: Melissa Findlay

Who is most likely to get Achondroplasia? Achondroplasia is an autosomal dominant condition. This means that an achondroplasic child can be born from one of the three possible ways. The first is if one of the parents has the disorder and the other is a big person. In this case there is a fifty percent chance that the child will be born a little person and a fifty percent chance that it will be born a big person. If both parents are little people they would have also have a fifty percent chance of having an Achondroplasic child. However they would only have a twenty five percent chance of having a big person. The other twenty five percent would be born homozygous dominant. These children are said to have homozygous Achondroplasia. This condition is almost always lethal in the first year of life and virtually all are spontaneously aborted at birth. The last possible way of having a child with this disorder is when two big people give birth to a little person. Seventy five percent of the little people living today came about due to this process. This process is known as a new mutation and occurs when the sperm is somehow develops into carrying the achondroplasic allele. Once this happens it is just as if one of parents is carrying the gene

Continued.. Achondroplasia is a disorder of bone growth that causes the most common type of dwarfism. It can be inherited as either a sex linked trait or a autosomal dominant trait, which means that if a child gets the defective gene from one parent, the child will have the disorder

Symptoms All people with Achondroplasia have a short stature. The average height of an adult male with Achondroplasia is 131 centimeters (52 inches, or 4 feet 4 inches), and the average height of an adult female with Achondroplasia is 124 centimeters (49 inches, or 4 feet 1 inch). An average-size trunk. Short arms and legs with particularly short upper arms and thighs. An enlarged head (macrocephaly) with a prominent forehead. Fingers are typically short. The ring finger and middle finger may diverge, giving the hand a three-pronged (trident) appearance. People with Achondroplasia are generally of normal intelligence.

How common is Achondroplasia? Achondroplasia affects about 1 in 25,000 people.

Life threatening? Since two copies are fatal, if two people with Achondroplasia dwarfism have children, there's a 1 in 4 chance of it dying shortly after birth

Can you be tested? If you have a parent with dwarfism, It is strongly encouraged you and your short statured parent to have a genetic consult. By testing the parent or family member with dwarfism, they would have a better idea of which genes you might or might not be carrying. A large number of the cases of Dwarfism are also due to random mutations with no family history. Genes that can be passed on, but not in either parent.

Is there treatment? Currently, there is no way to prevent or treat Achondroplasia, since the majority of cases result from unexpected new mutations. Treatment with growth hormone does not substantially affect the height of an individual with Achondroplasia. Leg-lengthening surgeries may be considered, in some very specialized cases.

Are there support groups? ia-Dwarfism/support-group ia-Dwarfism/support-group o/Support_Groups/Achondroplasia.htm o/Support_Groups/Achondroplasia.htm

Interesting facts Achondroplasia, which means "without cartilage formation", is a Greek word. Achondroplasia is part of a group of disorders called chrondrodystrophies. 80% of Achondroplasia cases are caused by spontaneous mutations. It is one of the most common of all skeletal dysplasia's Achondroplasia is the most common type of dwarfism, affecting up to 80% of all little people. Most Achondroplastics are double jointed, which is caused by loose ligaments. People with Achondroplasia usually have normal intelligence Men's average height is 51.8 inches tall which is about 4 ft. 3 Women's average height is 48.6 inches tall which is about 4 ft. Achondroplastics seldom ever reach five feet high. Nine out of ten children with Achondroplasia have normal sized parents. Usually average sized kids with Achondroplastics parents are not at a higher risk of passing the disease to their children Absolute prevention is NOT possible The appearance of Achondroplasia is apparent at birth. Infants who are homozygous Achondroplasia rarely live beyond a few months The greatest shortening occurs in the bone between the shoulder and elbow (humorous) and the bone between the hip and knee (femur )

Bibliography Achondroplasia Genetic Disorder Information on MedicineNet.com." Web. 26 Jan Achondroplasia." Packard Children's Hospital at Stanford LPCH: Northern California Children's Hospital. Web. 26 Jan Medicineplus.com. Web. 26 Jan