Noonan syndrome

Noonan syndrome (NS) is a genetic disorder that may present with mildly unusual facial features, short height, congenital heart disease, bleeding problems, and skeletal malformations. Facial features include widely spaced eyes, light-colored eyes, low-set ears, a short neck, and a small lower jaw. Heart problems may include pulmonary valve stenosis. The breast bone may either protrude or be sunken, while the spine may be abnormally curved. Intelligence is often normal. Complications of NS can include leukemia. A number of genetic mutations can result in Noonan syndrome. The condition may be inherited as an autosomal dominant condition or occur as a new mutation. Noonan syndrome is a type of RASopathy, the underlying mechanism for which involves attenuation of the RAS/MAPK cell signaling pathway. The diagnosis may be suspected based on symptoms, medical imaging, and blood tests. Confirmation may be achieved with genetic testing. No cure for NS is known. Treatment is based on the symptoms and underlying problems, and extra support in school may be required. Growth hormone therapy during childhood can increase an affected person's final height. Long-term outcomes typically depend on the severity of heart problems. An estimated 1 in 1000 people are mildly affected by NS, while about 1 in 2,000 have a more severe form of the condition. Males appear to be affected more often than females. The condition was named after American pediatric cardiologist Jacqueline Noonan, who described her first case in 1963. The most common signs leading to the diagnosis of Noonan syndrome are unique facial characteristics and musculoskeletal features. The facial characteristics are most prominent in infancy, becoming less apparent with age in many people with Noonan syndrome. Some of the characteristic features of Noonan syndrome include a large head with excess skin on the back of the neck, low hairline at the nape of the neck, high hairline at the front of the head, triangular face shape, broad forehead, and a short, webbed neck.

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Noonan syndrome

Medical genetics

Medical genetics is the branch of medicine that involves the diagnosis and management of hereditary disorders. Medical genetics differs from human genetics in that human genetics is a field of scientific research that may or may not apply to medicine, while medical genetics refers to the application of genetics to medical care. For example, research on the causes and inheritance of genetic disorders would be considered within both human genetics and medical genetics, while the diagnosis, management, and counselling people with genetic disorders would be considered part of medical genetics.

Short stature

Short stature refers to a height of a human which is below typical. Whether a person is considered short depends on the context. Because of the lack of preciseness, there is often disagreement about the degree of shortness that should be called short. Dwarfism is the condition of being very short, often caused by a medical condition. In a medical context, short stature is typically defined as an adult height that is more than two standard deviations below a population’s mean for age and gender, which corresponds to the shortest 2.