There are several potential causes of achondroplasia. The first is a genetic mutation on chromosome 4 of the fibroblast growth factor receptor 3 (FGFR3). Scientists do not know why this mutation occurs. The disorder can also be passed on from an affected parent. If one parent has the disorder they have a 50% chance of having an affected child. If both parents have the disorder they have a 50% chance of having an affected child, a 25% chance of having a normal child, and a 25% chance that they will have a child that inherits one abnormal gene from each parent resulting in severe skeletal abnormalities that lead to early death for that child. (1, 2) Statistics
Affects about 1 in 15,000 to 1 in 40,000 live births every year and can affect either sex. It can occur in all races and equally affects men and woman. About 10,000 people in the US are affected. About 80% of all little people have achondroplasia, about 190,000 people worldwide have the disorder, and 150,000 of those people have achondroplasia. (2, 3) Symptoms/Features of the Disorder
There are numerous physical features that a person with the disease will display. Hallmarks of the disorder are abnormal hands with a space between the long and ring fingers, bowed legs, and decreased muscle tone. They will have disproportionately large heads compared to their bodies and very prominent foreheads. They will also have shortened legs and arms with short stature, spinal stenosis, and spine curvatures called lordosis and kyphosis. (4) Disease Diagnosis
The diagnosis can be based on the physical features that are evident at birth. Before birth, fetal ultrasounds can also show the physical features. Diagnosis before birth is also done by examining the body cells of the baby; a DNA test of those cells can confirm or deny if the child will have achondroplasia when put through a procedure called chorionic villus sampling. (5) Treatments/ Cures/ Preventions
Although there is no current...