Fibrodysplasia ossificans progressiva is a autosomal dominant disorder that is most commonly acquired through spontaneous mutations of a specific gene found on chromosome 2.
Dominance is really just the relationship between two "alleles" on a certain gene, with one allele expressing dominance over the other.
The gene in question, Activin Receptor Type 1A (ACVR1), is a protein in the cells that controls bone morphogenetic proteins (BMP's). The random mutation changes codon 206 from arginine to histidine on the receptor protein.
In essence, the mutation changes the receptor protein to encode the BMP's to create an extra skeleton.
As FOP is a spontaneous mutation, there will not necessarily be a previous family history with the disorder in order for it to pop up. Very few FOP cases are inherited from parents because most people afflicted with FOP either are unable or choose not to have children.
One thing you must know about FOP: you either have it or you don't! Such is the case with autosomal dominant patterns.
Next, I am going to show you a few situations using Punnett Squares. If you do not know how to follow Punnett Squares, please view http://mhhe.com/biosci/genbio/virtual_labs_2K8/pages/PunnettSquares.html to get a basic understanding of them.
F=FOP
f=Normal
FF=Homozygous Dominant (will have FOP)
Ff=Heterozygous (will have FOP)
ff=Homozygous Recessive (will not have FOP)
An FF male with FOP has children with an ff normal female.
Child Results: Ff, Ff, Ff, Ff
Therefore, all of their children will be afflicted with FOP because the dominant F is expressed.
An ff normal male has children with an Ff female with FOP.
Child Results: Ff, ff, Ff, ff
Therefore, there is a 50% chance of their children having FOP because the dominant F is expressed in half of the results.
An Ff male with FOP has children with an Ff female with FOP.
Child Results: FF, Ff, Ff, ff
Therefore, there is a 75% chance of their children having FOP because the dominant F is expressed in 3/4 of the results.
Statistics
Scientists estimate that 1 in 2 million people are afflicted with FOP worldwide.
This is an estimated 2,500 to 3,500 cases. To put this into perspective, you would have to fill 20 football stadiums, housing 100,000 people each, to find one person with FOP.
If you found the out-of-place dot, then you found one person with FOP in a crowd of 2 million people.
There have been about 800 confirmed cases of FOP globally.
About 30% of these cases come from the U.S. alone.
FOP does not follow any ethnic, racial, or gender patterns whatsoever.
Anyone can get it.
As FOP is a spontaneous mutation, there will not necessarily be a previous family history with the disorder in order for it to pop up. Very few FOP cases are inherited from parents because most people afflicted with FOP either are unable or choose not to have children.
One thing you must know about FOP: you either have it or you don't! Such is the case with autosomal dominant patterns.
Next, I am going to show you a few situations using Punnett Squares. If you do not know how to follow Punnett Squares, please view http://mhhe.com/biosci/genbio/virtual_labs_2K8/pages/PunnettSquares.html to get a basic understanding of them.
F=FOP
f=Normal
FF=Homozygous Dominant (will have FOP)
Ff=Heterozygous (will have FOP)
ff=Homozygous Recessive (will not have FOP)
An FF male with FOP has children with an ff normal female.
Child Results: Ff, Ff, Ff, Ff
Therefore, all of their children will be afflicted with FOP because the dominant F is expressed.
An ff normal male has children with an Ff female with FOP.
Child Results: Ff, ff, Ff, ff
Therefore, there is a 50% chance of their children having FOP because the dominant F is expressed in half of the results.
An Ff male with FOP has children with an Ff female with FOP.
Child Results: FF, Ff, Ff, ff
Therefore, there is a 75% chance of their children having FOP because the dominant F is expressed in 3/4 of the results.
Statistics
Scientists estimate that 1 in 2 million people are afflicted with FOP worldwide.
This is an estimated 2,500 to 3,500 cases. To put this into perspective, you would have to fill 20 football stadiums, housing 100,000 people each, to find one person with FOP.
If you found the out-of-place dot, then you found one person with FOP in a crowd of 2 million people.
There have been about 800 confirmed cases of FOP globally.
About 30% of these cases come from the U.S. alone.
FOP does not follow any ethnic, racial, or gender patterns whatsoever.
Anyone can get it.
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