17 January 1997

Hi everybody,

We have seen a mother and her son with Noonan syndrome. Another sister, apparently unaffected by Noonan syndrome, has bilateral retinoblastoma. The mother is pregnant.

1. Does anybody have suggestions as to a possible connection between the two conditions ?

2. Can anybody help in prenatal diagnosis of Noonan syndrome?

3. What is the recurrence risk of sporadic retinoblastoma?

Thanks for your help.