I looked it up and in bare bones this is what I came across.
Noonan Syndrome is a relatively common congenital genetic condition which affects both males and females. The principal features include congenital heart malformation, short stature, learning problems, indentation of the chest, impaired blood clotting, and a characteristic configuration of facial features. It is believed that between approximately 1 in 1,000 and 1 in 2,500 children worldwide are born with NS. It is one of the most common genetic syndromes associated with congenital heart disease, similar in frequency to Down syndrome. However, the range and severity of features can vary greatly in patients with NS. Therefore, the syndrome is not always identified at an early age.
Recurrence in siblings and apparent transmission from parent to child has long suggested a genetic defect with autosomal dominant inheritance and variable expression. A person with NS has up to a 50% chance of transmitting it to a child. The fact that an affected parent is not always identified for children with NS suggests several possibilities:
a parent could carry the gene without being affected (incomplete penetrance)
manifestations are variably expressed and could be so subtle as to go unrecognized (variable expressivity)
a high proportion of cases represent new or sporadic mutation.
So although it's not life threatening it is very common to have NS apparently. I think pretty much the baby has a 50/50 chance of having NS syndrome but it might not be a bad inheritance, i.e. slight learning disabilities or not grow quite as tall as class mates etc. Baby might be born without it but remain a carrier and pass it onto his/her children in years to come. Hard to say but from reading it's widely known about and not life threatening etc!
Hope that helps. I don't know anyone with the condition.
