How to you get Noonan syndrome?
Many individuals with Noonan syndrome have a de novo (brand new) pathogenic variant. An affected parent is identified in 30%-75% of families.
Noonan syndrome is inherited in an autosomal dominant manner. This means that one copy of a gene change is enough to cause symptoms of the condition. Once an individual is identified with an autosomal dominant condition (such as Noonan syndrome) each of their future children has a 50% risk to inherit the same gene change.