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Genetic conditions, inheritance and related genes, with original NLM summaries.
Glaucoma is a group of eye disorders in which the optic nerves connecting the eyes and the brain are progressively damaged. This damage can lead to reduction in side (peripheral) vision and eventual blindness. Other signs and symptoms…
Cystic fibrosis is an inherited disease characterized by the buildup of thick, sticky mucus that can damage many of the body's organs. The disorder's most common signs and symptoms include progressive damage to the respiratory system…
Hypertrophic cardiomyopathy is a heart condition characterized by thickening (hypertrophy) of the heart (cardiac) muscle. When multiple members of a family have the condition, it is known as familial hypertrophic cardiomyopathy.…
Harlequin ichthyosis is a severe genetic disorder that affects the skin. Infants with this condition are born prematurely with very hard, thick skin covering most of their bodies. The skin forms large, diamond-shaped plates that are…
Congenital hypothyroidism is a partial or complete loss of function of the thyroid gland (hypothyroidism) that affects infants from birth (congenital). The thyroid gland is a butterfly-shaped tissue in the lower neck. It makes…
Lactose intolerance is a condition that makes it difficult to digest lactose, a sugar found in milk and several other dairy products. Lactose is normally broken down by an enzyme called lactase, which is produced by cells in the…
Juvenile idiopathic arthritis refers to a group of conditions involving joint inflammation (arthritis) that first appears before the age of 16. This condition is an autoimmune disorder, which means that the immune system malfunctions…
Cystinuria is a condition characterized by the buildup of the amino acid cystine, a building block of most proteins, in the kidneys and bladder. As the kidneys filter blood to create urine, cystine is normally absorbed back into the…
Spinal muscular atrophy is a genetic disorder characterized by weakness and wasting (atrophy) in muscles used for movement (skeletal muscles). It is caused by a loss of specialized nerve cells, called motor neurons that control muscle…
Retinoblastoma is a rare type of eye cancer that usually develops in early childhood, typically before the age of 5. This form of cancer develops in the retina, which is the specialized light-sensitive tissue at the back of the eye…
Familial exudative vitreoretinopathy is a hereditary disorder that can cause vision loss that worsens over time. This condition affects the retina, the specialized light-sensitive tissue that lines the back of the eye. In people with…
Idiopathic pulmonary fibrosis is a chronic, progressive lung disease. This condition causes scar tissue (fibrosis) to build up in the lungs, which makes the lungs unable to transport oxygen into the bloodstream effectively. The…
Familial restrictive cardiomyopathy is a genetic form of heart disease. For the heart to beat normally, the heart (cardiac) muscle must contract and relax in a coordinated way. Oxygen-rich blood from the lungs travels first through…
Hidradenitis suppurativa, also known as acne inversa, is a chronic skin disease characterized by recurrent boil-like lumps (nodules) under the skin. The nodules become inflamed and painful. They tend to break open (rupture), causing…
Central precocious puberty is a condition that causes early sexual development in girls and boys. While puberty normally starts between ages 8 and 13 in girls and between ages 9 and 14 in boys, girls with central precocious puberty…
Wilson disease is an inherited disorder in which excessive amounts of copper accumulate in the body, particularly in the liver, brain, and eyes. The signs and symptoms of Wilson disease usually first appear between the ages of 6 and…
Psoriatic arthritis is a condition involving joint inflammation (arthritis) that usually occurs in combination with a skin disorder called psoriasis. Psoriasis is a chronic inflammatory condition characterized by patches of red,…
Gitelman syndrome is a kidney disorder that causes an imbalance of charged atoms (ions) in the body, including ions of potassium, magnesium, and calcium. The signs and symptoms of Gitelman syndrome usually appear in late childhood or…
Friedreich ataxia is a genetic condition that affects the nervous system and causes movement problems. People with this condition develop impaired muscle coordination (ataxia) that worsens over time. Other features of this condition…
Li-Fraumeni syndrome is a rare disorder that greatly increases the risk of developing several types of cancer, particularly in children and young adults. The cancers most often associated with Li-Fraumeni syndrome include breast…
Lattice corneal dystrophy type I is an eye disorder that affects the clear, outer covering of the eye called the cornea. The cornea must remain clear for an individual to see properly; however, in lattice corneal dystrophy type I,…
Primary ciliary dyskinesia is a disorder that is characterized by chronic respiratory tract infections, abnormally positioned internal organs, and difficulties having biological children (decreased fertility). The signs and symptoms…
Hypertension is abnormally high blood pressure in the arteries, which are the blood vessels that carry blood from the heart to the rest of the body. As the heart beats, it forces blood through the arteries to deliver nutrients and…
Lamellar ichthyosis is a condition that mainly affects the skin. Infants with this condition are typically born with a tight, clear sheath covering their skin called a collodion membrane. This membrane usually dries and peels off…
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