Tên chính thức của gen TP53 là gì?Tên chính thức của gen này là "khối u protein p53."TP53 là biểu tượng chính thức của gen. TP53 gen cũng được biết đến bằng tên khác, được liệt kê dưới đây.Tìm hiểu thêm về gen tên và biểu tượng trên về trang.Các chức năng bình thường của gen TP53 là gì?Gen TP53 cung cấp hướng dẫn cho việc thực hiện một protein được gọi là khối u protein p53 (hoặc p53). Protein này hoạt động như một ức chế khối u, có nghĩa là nó quy định phân chia tế bào bằng cách giữ các tế bào phát triển và phân chia quá nhanh hoặc một cách không kiểm soát được.P53 protein nằm trong nhân tế bào khắp cơ thể, nơi mà nó gắn (binds) trực tiếp đến DNA. Khi DNA trong một tế bào trở nên bị hỏng do các đại lý như hóa chất độc hại, bức xạ, hoặc tia cực tím (UV) từ ánh sáng mặt trời, protein này đóng một vai trò quan trọng trong việc xác định cho dù các DNA sẽ được sửa chữa hoặc các tế bào bị hư hỏng sẽ hủy (trải qua apoptosis). Nếu các DNA có thể được sửa chữa, p53 sẽ kích hoạt các gen để sửa chữa những thiệt hại. Nếu các DNA không thể được sửa chữa, protein này ngăn các tế bào phân chia và tín hiệu nó phải trải qua quá trình chết rụng. Bằng cách ngăn chặn các tế bào với đột biến hoặc bị hư hại DNA từ phân chia, thị trấn này có p53 giúp ngăn ngừa sự phát triển của khối u.Bởi vì p53 là điều cần thiết cho việc điều chỉnh phân chia tế bào và ngăn ngừa khối u hình thành, nó đã được đặt tên là "người giám hộ của bộ gen."Làm thế nào có thay đổi trong TP53 gen liên quan đến điều kiện sức khỏe?breast cancer - increased risk from variations of the TP53 geneInherited changes in the TP53 gene greatly increase the risk of developing breast cancer as part of a rare cancer syndrome called Li-Fraumeni syndrome (described below). These inherited mutations are thought to account for less than 1 percent of all breast cancer cases.Non-inherited (somatic) mutations in the TP53 gene are much more common, occurring in approximately 20 to 40 percent of all breast cancer cases. These somatic mutations are acquired during a person's lifetime and are present only in tumor cells. The cancers associated with somatic mutations are typically not inherited and do not occur as part of a cancer syndrome. Many of these mutations change single protein building blocks (amino acids) in the p53 protein. These mutations lead to the production of a nonfunctional version of this protein. The defective protein builds up in cells and cannot regulate cell growth and division.In some cases of breast cancer, one copy of the TP53 gene is lost and the remaining copy has a mutation that prevents the cell from producing any p53. Without this protein, DNA damage accumulates and cells divide in an uncontrolled way, leading to a cancerous tumor. Mutations in the TP53 gene are associated with larger tumors and more advanced disease than breast cancers without TP53 mutations. Recurring tumors are also more likely to have mutations in the TP53 gene.bladder cancer - associated with the TP53 geneSomatic TP53 gene mutations in bladder cells have been found in some cases of bladder cancer. Most of these mutations change single amino acids in p53. The altered protein cannot bind to DNA, preventing it from effectively regulating cell growth and division. As a result, DNA damage accumulates in cells. These abnormal cells may divide in an uncontrolled way, leading to the growth of a cancerous tumor. Mutations in the TP53 gene may help predict whether bladder cancer will progress and spread to nearby tissues, and whether the disease will recur after treatment.head and neck squamous cell carcinoma - associated with the TP53 geneSomatic mutations in the TP53 gene have been found in nearly half of all head and neck squamous cell carcinomas (HNSCC). This type of cancerous tumor occurs in the moist lining of the mouth, nose, and throat. Most of the TP53 gene mutations involved in HNSCC change single amino acids in p53; these changes impair the protein's function. Without functioning p53, DNA damage builds up in cells, and they can continue to divide without control, leading to tumor formation.Li-Fraumeni syndrome - associated with the TP53 geneAlthough somatic mutations in the TP53 gene are found in many types of cancer, Li-Fraumeni syndrome appears to be the only cancer syndrome associated with inherited mutations in this gene. More than 60 different mutations in the TP53 gene have been identified in individuals with Li-Fraumeni syndrome. These mutations are typically inherited from a parent and are present in all of the body's cells.Many of the mutations associated with Li-Fraumeni syndrome change single amino acids in the part of the p53 protein that binds to DNA. Other mutations delete small amounts of DNA from the gene. Mutations in the TP53 gene lead to a version of p53 that cannot effectively regulate cell growth and division. Specifically, the altered protein is unable to trigger apoptosis in cells with mutated or damaged DNA. As a result, DNA damage can accumulate in cells. Such cells may continue to divide in an uncontrolled way, leading to the growth of tumors.
other cancers - associated with the TP53 gene
Somatic mutations in the TP53 gene are the most common genetic changes found in human cancer, occurring in about half of all cancers. In addition to the cancers described above, TP53 mutations have been identified in several types of brain tumor, colorectal cancer, a type of bone cancer called osteosarcoma, a cancer of muscle tissue called rhabdomyocarcinoma, and a cancer called adrenocortical carcinoma that affects the outer layer of the adrenal glands (small hormone-producing glands on top of each kidney).
Most TP53 mutations change single amino acids in the p53 protein, which leads to the production of an altered version of the protein that cannot bind effectively to DNA. This defective protein can build up in the nucleus of cells and prevent them from undergoing apoptosis in response to DNA damage. The damaged cells continue to grow and divide in an unregulated way, which can lead to cancerous tumors.
Where is the TP53 gene located?
Cytogenetic Location: 17p13.1
Molecular Location on chromosome 17: base pairs 7,668,401 to 7,687,549
The TP53 gene is located on the short (p) arm of chromosome 17 at position 13.1.
The TP53 gene is located on the short (p) arm of chromosome 17 at position 13.1.
More precisely, the TP53 gene is located from base pair 7,668,401 to base pair 7,687,549 on chromosome 17.
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