Noonan syndrome
Noonan syndrome can affect a person in many different ways.Not everyone with the disorder willshare the same characteristics.
The three most common characteristics of Noonan syndrome are:
These are discussed in more detail below.
People with Noonan syndrome may have a characteristic facial appearance, although this isn't always the case.
The following features may become apparent soon after birth:
Children with Noonan syndromealso have abnormalities that affect the bones of the chest. For example,their chest may stick out or sink in, or they may have an usually wide chest with a large distance between the nipples.
These featuresmay be more obvious in early childhood, but tend to become muchless noticeable inadulthood.
Children with Noonan syndromeare usually a normal length at birth. However, at around two years old you may notice that they don't grow as quickly as other children of the same age.
Puberty (when a child begins to mature sexually and physically) typically occurs a few years later than normal andthe expected growth spurt that normally happens during puberty is either reduced or doesnt happen at all.
Medication known ashuman growth hormone can sometimes help children reach a more normal height. Left untreated, the average adult heightfor men with Noonan syndrome is 162.5cm (5ft 3in) and for women is 153cm (5ft).
Mostchildren with Noonan syndrome will have some form of congenital heart disease. This is usually one of the following:
Overall, the risk of developing cancer doesnt appear to be much higher than for people without Noonan syndrome, although there may be a very small increased risk of some rare childhood cancers.
Read about Noonan syndrome - a genetic disorder that causes a wide range of features, such as heart abnormalities and unusual facial features.
Read about the main features of Noonan syndrome, including unusual facial features, short stature and heart defects.
Read about what causes Noonan syndrome, and what the chances are of the condition being passed on.
Read about how Noonan syndrome is diagnosed, including what tests you or your child may have.
Read about the treatments available for the different problems associated with Noonan syndrome.