How Rare is Duane's Syndrome?

Is there any proven or anecdotal link between Down syndrome and fraternal or sororal disability?

• I ask this question sympathetically and with the best possible intentions, but I understand it might come across as a little blunt (for which I apologise). I know 7 different people who have Down syndrome. All of them have at least 1 brother or sister, and in all of those 7 cases the brother or sister has some recognised disability. In most cases, it is a learning disability (including autism/aspergers). In some, there is a wider family history of disability (severe, in fact). I understand that Down syndrome is not 'hereditary' per se, but at the same time it is my understanding that Translocation Down Syndrome makes up approximately 4 - 5% of all Down Syndrome cases and that this form of Down Syndrome very much IS hereditary (from an unaffected parent to the DS child). My question, therefore, is as follows: Is there any link - either proven or currently in research - that connects Down Syndrome in one sibling with disability in other siblings within that family? Or - in other words - is the fact that all of those people I know who have DS all have a sibling with a substantial learning or physical disability a pure co-incidence, or is there some causal link which researchers haven't fully understood through their work at this time?

• Answer:

  I believe this is coincidental more than anything else.  But I do w... You must be signed in to read this answer.Connected to GoogleConnected to FacebookBy continuing you indicate that you have read and agree to the .  Loading account...Complete Your ProfileFull NameChecking...EmailChecking...PasswordChecking...By creating an account you indicate that you have read and agree to the .