Noonan syndrome refers to a genetic defect that arrests normal growth and development of different parts of the affected person’s body. the signs, symptoms, and characteristics of Noonan syndrome vary widely among people. (1)
Can You Detect Noonan Syndrome Before Birth?
Noonan syndrome can be detected before birth with the use of prenatal molecular genetic testing methods, which include chorionic villus sampling (CVS) or amniocentesis.
DNA is separated from the cells of the growing baby through one of these two procedures and is then studies for the disease-causing mutation or alterations. If a mutation is present, the parents are then counseled, and they can decide with proper consultation whether to carry the pregnancy to the full term or to terminate the pregnancy (2)
Another method by which genetic testing can be done is preimplantation genetic diagnosis (PGD). This is carried out for couples who undergo in-vitro fertilization in order to attain pregnancy. Embryos can be tested for any genetic mutations or abnormalities before transferring them into the uterus. Embryos without any genetic alterations only would be transferred into the uterus and would be implanted (2)
Is Noonan Syndrome More Common In Males Or Females?
Noonan syndrome is not known to affect a particular race or sex more than the other. It is a syndrome that occurs in about 1 in every 2500 live births and qualifies as an extremely rare disease. (2)
The signs and symptoms of Noonan syndrome differ greatly among people. These may range from mild to severe. Also, the specific gene or genes that have been affected may be a deciding factor for the characteristics and symptoms an affected individual will produce. Some of the most common signs and symptoms seen in a Noonan syndrome person may include-
Abnormal Facial Features-
It is one of the most prominent symptoms that prompt a diagnosis of Noonan syndrome
Abnormal facial features are more prominent in young children and infants. With age, the features become more subtle
These features may include wide-set eyes, droopy lids, low-set, and backward ears, nose which is depressed at the top and wide at the base, nose may also have a bulging tip, mouth with a deep furrow between the nose and the mouth, crooked teeth, small lower jaw, face appears hanging and impassive, head prominent, low back hairline, skin appears thin and kind of transparent with age
Heart Problems- Many people affected with Noonan syndrome also have some form of congenital heart disease. These may include valve disorders, hypertrophic cardiomyopathy or thickening of the heart muscle, structural defects of the heart like ventricular septal defect or hole in the heart, pulmonary artery stenosis. There may also be an irregular heart rhythm or arrhythmia
Growth Problems- Many kids with Noonan syndrome do not grow as well as they should. Short stature is quite common in people with Noonan syndrome. Due to eating difficulties, there is also poor weight gain
Musculoskeletal Problems- Oddly shaped chest, webbed neck, deformities of the spine, etc. are very common with Noonan syndrome
Learning Disabilities- Intelligence is not affected in most people with Noonan syndrome, however, there may be some learning difficulties and a broad range of emotional, mental and behavioral problems in some of them. Hearing and visual difficulties may further complicate learning
Eye And Hearing Problems- Structural abnormalities can cause eye and ear problems in kids affected with Noonan syndrome
Genital And Kidney Problems- Kids, especially males with Noonan syndrome may have genital and kidney problems
Skin Problems- Skin problems are common in Noonan syndrome (1)
Noonan syndrome can be detected before birth with the help of amniocentesis. It is not known to affect any particular race or sex more than the other. Noonan syndrome is quite a rare disorder.