Achondroplasia dwarfism is the most common type of drawfism. The term achondroplasia is formed from a Greek world that means without cartilage formation. Achondroplasia Dwarfism is basically a bone growth disorder. While the Greek name would lend you to believe that the problem lies with the cartilage that is not the case with this type of dwarfism. The problem is actually that the cartilage has a difficult time converting to bone. This difficulty is especially apparent in the longer bones of the body such as is found in the arms and legs.
The interesting thing is that most of the people who are diagnosed with achondroplasia dwarfism often have average sized parents. This is because the condition is caused by a new mutation in the fibroblast growth factor receptor 3 gene; this gene is also referred to as the FGFR3 gene. This is the specific gene that is thought to be responsible for Achondroplasia Dwarfism, although there is no explanation for why the mutation in these genes occurs in some people but not in others.
Achondroplasia dwarfism can also be inherited in an autosomal dominant pattern. What this means is that one copy of the altered gene in each cell is enough to cause the disorder in the developing fetus. In these circumstances, one of the parents with Achondroplasia Dwarfism passes on the gene to the child.
If one parent has achondroplasia dwarfism than the child has a 50% chance of inheriting the FGFR3 gene. If both parents have achondroplasia dwarfism then a child will have a one in four chance of inheriting the gene from both parents. Children that inherit the gene from both parents are considered to have a severe form of achondroplasia dwarfism and generally will not live for more than 12 months after birth. While achondroplasia dwarfism can be inherited, inherited genes do not account for most of the new cases. In fact, 80% of the cases of this type of dwarfism are due to new mutations of the gene that cannot be explained.
Achondroplasia dwarfism is usually characterized by a very short stature. Adult males with the condition will usually average about four feet four inches and females will average about four feet one inch. This form of dwarfism is characterized by an average sized trunk, short arms and legs, very short upper arms and thighs, an enlarged head with a very prominent forehead, and short fingers.
Individuals with achondroplasia dwarfism often suffer from some health problems but all mental capabilities are that of any other human being. Many will develop apnea and other breathing disorders, and reduced muscle strength is also common. In addition, obesity, recurrent ear infections, and crowded teeth are very common. Some individuals will experience all of these things while others may only suffer from a swaying of the lower back and bowed legs due to their body composition. Depending on the severity of the swaying back and bowing of the legs, walking and standing may be difficult.
There is not a cure for achondroplasia dwarfism but most people are able to live happy, healthy, fulfilling lives despite the diagnosis. Achondroplasia dwarfism is quite common affecting one in 15,000 to 40,000 births, depending on where you take your population sampling from. In two to five percent of cases newborns will not survive, but most individuals will go on to have a normal life span. Though being short and the shorter arms and legs can prove challenging, most individuals are able to do the things that everyone else of average heights and builds can.