Hutchinson-Gilford progeria syndrome (HGPS) is characterized by clinical features that typically develop in childhood and resemble some features of accelerated aging. Children with HGPS usually appear normal at birth. Profound failure to thrive occurs during the first year. Characteristic facial features include head that is disproportionately large for the face, narrow nasal ridge, narrow nasal tip, thin vermilion of the upper and lower lips, small mouth, and retro- and micrognathia. Common features include loss of subcutaneous fat, delayed eruption and loss of primary teeth, abnormal skin with small outpouchings over the abdomen and upper thighs, alopecia, nail dystrophy, coxa valga, and progressive joint contractures. Later findings include low-frequency conductive hearing loss, dental crowding, and partial lack of secondary tooth eruption. Motor and mental development is normal. Death occurs as a result of complications of severe atherosclerosis, either cardiac disease (myocardial infarction or heart failure) or cerebrovascular disease (stroke), generally between ages six and 20 years. Average life span is approximately 14.5 years.

Any coronary artery disease in which the cause of the disease is a mutation in the LRP6 gene.

Aortic aneurysms usually have no symptoms. However, depending on the size, growth rate, and location of these abnormalities, they can cause pain in the jaw, neck, chest, or back; swelling in the arms, neck, or head; difficult or painful swallowing; hoarseness; shortness of breath; wheezing; a chronic cough; or coughing up blood. Aortic dissections usually cause severe, sudden chest or back pain, and may also result in unusually pale skin (pallor), a very faint pulse, numbness or tingling (paresthesias) in one or more limbs, or paralysis.\n\nFamilial thoracic aortic aneurysm and dissection (familial TAAD) involves problems with the aorta, which is the large blood vessel that distributes blood from the heart to the rest of the body. Familial TAAD affects the upper part of the aorta, near the heart. This part of the aorta is called the thoracic aorta because it is located in the chest (thorax). Other vessels that carry blood from the heart to the rest of the body (arteries) can also be affected.\n\nIn familial TAAD, the aorta can become weakened and stretched (aortic dilatation), which can lead to a bulge in the blood vessel wall (an aneurysm). Aortic dilatation may also lead to a sudden tearing of the layers in the aorta wall (aortic dissection), allowing blood to flow abnormally between the layers. These aortic abnormalities are potentially life-threatening because they can decrease blood flow to other parts of the body such as the brain or other vital organs, or cause the aorta to break open (rupture).\n\nThe occurrence and timing of these aortic abnormalities vary, even within the same affected family. They can begin in childhood or not occur until late in life. Aortic dilatation is generally the first feature of familial TAAD to develop, although in some affected individuals dissection occurs with little or no aortic dilatation.\n\nFamilial TAAD may not be associated with other signs and symptoms. However, some individuals in affected families show mild features of related conditions called Marfan syndrome or Loeys-Dietz syndrome. These features include tall stature, stretch marks on the skin, an unusually large range of joint movement (joint hypermobility), and either a sunken or protruding chest. Occasionally, people with familial TAAD develop aneurysms in the brain or in the section of the aorta located in the abdomen (abdominal aorta). Some people with familial TAAD have heart abnormalities that are present from birth (congenital). Affected individuals may also have a soft out-pouching in the lower abdomen (inguinal hernia), an abnormal curvature of the spine (scoliosis), or a purplish skin discoloration (livedo reticularis) caused by abnormalities in the tiny blood vessels of the skin (dermal capillaries). However, these conditions are also common in the general population. Depending on the genetic cause of familial TAAD in particular families, they may have an increased risk of developing blockages in smaller arteries, which can lead to heart attack and stroke.

A rare, genetic form of obesity characterized by morbid obesity, hypertension, type 2 diabetes mellitus and dyslipidemia leading to early coronary disease, myocardial infarction and congestive heart failure. Intellectual disability and decreased sperm counts or azoospermia have also been reported.

Hyperlipoproteinemia type ID is a rare autosomal recessive disorder characterized by impaired clearance of triglyceride (TG)-rich lipoproteins in plasma, leading to severe hypertriglyceridemia (chylomicronemia). Clinical features include eruptive xanthomas, lipemia retinalis, hepatosplenomegaly, episodes of abdominal pain, and pancreatitis. Onset usually occurs in adulthood (summary by Brahm and Hegele, 2013). For a discussion of genetic heterogeneity of familial chylomicronemia, see 238600.

Sitosterolemia, also known as phytosterolemia, is an autosomal recessive metabolic condition characterized by unrestricted intestinal absorption of both cholesterol and plant-derived cholesterol-like molecules, such as sitosterol. Patients with this disorder have very high levels of plant sterols in the plasma and develop tendon and tuberous xanthomas, accelerated atherosclerosis, and premature coronary artery disease (summary by Berge et al., 2000). For a general phenotypic description and a discussion of genetic heterogeneity of sitosterolemia, see 210250.

Any ypoalphalipoproteinemia in which the cause of the disease is a mutation in the ABCA1 gene.

Primary hypoalphalipoproteinemia-2 is an autosomal recessive disorder characterized by dysfunctional apoA-I production, resulting in undetectable levels of apoA-I in serum and in markedly low levels of serum high density lipoprotein cholesterol (HDL-C). The disorder is associated with extensive atherosclerosis, xanthomas, and corneal opacities (summary by Tanaka et al., 2018). For a discussion of genetic heterogeneity of primary hypoalphalipoproteinemia, see 604091.