Is MECP2 Duplication syndrome a rare condition?
Currently, diagnosed cases are very rare, but its rarity seems to be due mostly to the fact that the vast majority of cases are undiagnosed. That will no doubt change drastically in the next 5 or 10 years. With more testing many more cases will be diagnosed. It is hard to estimate how common it will become. It will probably remain a lot less common than Fragile-X or Down syndrome. Based on available information my very rough guess is that it will be found in about 1 out of every 75,000 boys. Of course, this only a semi-educated guess and the actual numbers could turn out to be a lot higher or a lot lower.
