Townes-Brocks syndrome ... (Townes-Brocks Syndrome) - Gen SALL1.
Syndrome Townes-Brocks of a genetic disease which affects many parts of the body. The most common features of this condition are clogging the anal orifice, ears abnormally and malformations affecting preferably hand thumb. Most people with this condition have at least two of these three main features.
Other possible signs and symptoms of this disease include mild to profound hearing loss, heart defects, kidney abnormalities and genital malformations. These characteristics vary among affected individuals, even within the same family. Also they have been reported in approximately 10% of those affected problems learning or intellectual disabilities.
This process is due to mutations in the gene SALL1, located on the long arm of chromosome 16 (16q12.1). The SALL1 gene is part of a group of genes SALL family. These genes encode proteins which act as transcription factors involved in the formation of tissues and organs during embryonic development. This protein is encoded in many tissues, including kidney, liver and fetal brain and adult. However, the exact function of the protein SALL1 is unclear. Based on the effects of mutations SALL1, it is believed that this protein plays an important role before birth in the development of hands, particularly the thumbs, ears, anus, kidneys and other body parts.
They have identified more than 55 mutations in the gene SALL1 in people with Townes-Brocks syndrome. These mutations result in decreased protein coding SALL1 or an abnormally small version malfunctioning within the cell. Alterations in gene SALL1 interfere with normal copies of the SALL1 protein, preventing into the nucleus to regulate gene activity. It is likely that this type of genetic change lead to the most serious cases of Townes-Brocks syndrome, whereas mutations that reduce the amount of protein SALL1 are probably responsible for milder cases. Because the SALL1 gene appears to be necessary for normal development of many different organs and tissues before birth, it helps explain why mutations in this gene prevents normal development of many organs and different tissues during embryonic development, resulting in the variety of birth defects associated with the syndrome Townes-Brocks of.
Syndrome Townes-Brocks of inherited as an autosomal dominant, which means that a copy of the altered gene in each cell is sufficient to express the alteration. In some cases, an affected person inherits the mutation from an affected parent. 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 syndrome Townes-Brocks of, by complete PCR amplification of exons SALL1 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).