Why did I get Fibrous Dysplasia/ McCune-Albright Syndrome (FD/MAS)?

We do not know why the FD/MAS mutation occurs. The gene involved in FD/MAS seems to be especially susceptible to mutations. Although FD/MAS is rare, it occurs in males and females and people of all races and all parts of the world. It is likely that the mutation occurs randomly. There is nothing that a parent did that caused or the FD/MAS mutation to occur.