Supravalvular aortic stenosis (Supravalvular aortic stenosis) - ELN gene.
Supravalvar aortic stenosis (SVAS) is a heart defect that develops before birth. This defect is aortic stenosis described supravalvar because the aortic section tapering is just above the aortic valve. Some people with SVAS also have defects in other blood vessels, most commonly the pulmonary artery stenosis. Often can be detected in people affected a heart murmur. SVAS If untreated, the narrowing of the aorta can cause shortness of breath, chest pain and, ultimately, heart failure. SVAS severity varies considerably, even among family members. Some affected individuals die in infancy, while others never show symptoms of the disease.
This process is due to mutations in ELN gene, located on the long arm of chromosome 7 (7q11.23). This gene codes tropoelastin protein. Multiple copies of this protein adhere to each other to form elastin. Elastin is the principal component of elastic fibers that provide strength and flexibility to connective tissue. The loss of a copy of the ELN gene reduces the production of elastin, which interrupts the normal structure of elastic fibers in many connective tissues.
They have identified at least 60 mutations in the gene responsible for ELN supravalvular aortic stenosis (SVAS). Most of the identified mutations encoding tropoelastin decrease. Tropoelastin deficiency reduces the amount of elastin mature protein that is processed and is available for the formation of elastic fibers. As a result, the elastic fibers making up the aorta are thinner than normal. To compensate, the smooth muscle cells lining the aorta increase in number, causing the aorta to become thicker and narrower than normal. Because of these changes, the aorta is less flexible and resistant to tension constant blood flow and heart pumping. Eventually, the wall of the aorta may be damaged. The narrowing of the aorta makes the heart work harder to pump blood through the aorta, which may cause difficulty breathing, chest pain, and ultimately heart failure.
This disease is inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to trigger the disease. However, some people who inherit the altered gene never develop the characteristics of SVAS. This situation is known as reduced penetrance. In some cases, a person inherits the mutation from a parent who has the mutation. Other cases are due to new mutations in the gene and occur in people with no history of disease in your family.
Tests in IVAMI: in IVAMI perform detection of mutations associated with supravalvular aortic stenosis (SVAS), by complete PCR amplification of the exons of the ELN gene, and subsequent sequencing.
Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).