From what reason was leukemia caused? 's general knowledge

From what reason was leukemia caused? 's general knowledge
The precise cause of disease of the human leukemia has not been bright so far. A lot of factors are thought to be involved in morbidity of leukemia. The virus may be a main factor. In addition, still have factors such as inherent cause, radiating, chemical poisonous substance or medicine,etc..
Abnormal state and emergence of leukemia of some chromosome have direct relations, fracture and transposition of the chromosome can make the position of the cancer gene move and are activated, the change of genetic structure can be caused directly mutation take place in cells in the chromosome, the reducing of the immunological function is favorable to the morbidity of leukemia.
(1)Virus
Verify the intersection of tumour and virus, RNA of Model C, or go against, it duplicates virus to be mammal such as little mouse, cat, ox, sheep, the intersection of primate and spontaneous cause of disease of leukemia already. This kind of virus can be against duplicating enzyme according to RNA replica whose order formated DNA through being endogenous, the virus, can bring out and cancerate after it inserts into the host's chromosome DNA.
Tumour and virus carry the virus source tumour gene (v-onc) ,Most vertebrates (including people's cells) There are genes with homology to v-onc that are called the source tumour gene in the genetic body. Can make the neighbouring gene cancerate after v-onc is combined into in the genetic body of the constellation chief cell. The infection of the virus can cause the source tumour gene to activate against duplicating, become the malignant gene that changed, cause target cells to cancerate. Enter the internal virus gene even not contain v-onc, if change the normal function of the gene, also may cause leukemia.
The cause of disease of virus of the human leukemia is studied, already had a history of several dozen years, but only grow up so far T cell leukemia must be caused by virus.
(2)Inherent cause
Inherent cause and some leukemia have illness coming on and have something to do with. The person who has family's history of leukemia accounts for 8.1% in the leukemia patient, and only 0.5% of control group. The morbidity of crowd's acute lymphocyte leukemia of consanguineous marriage is 30 times than expected value. The hereditary illness that some chromosome has distortion, ruptures is often with higher leukemia morbidity, if Down syndrome, inborn blood vessel expand Erythema (Bloom syndrome) With Fanconi anaemia,etc..
Acute lymphocyte leukemia patients 50% of children have a kind of special palm line, are called Sydney line. There is not a certain connection in leukemia and HLA antigen type, for instance acute lymphocyte leukemia often accompanies HLA-A2 and A9. There is a certain connection to explain the morbidity of inherent cause and leukemia, but for most leukemia, leukemia is not genetic disease after all.
(3)Radiate the factor
Ionization radiation causes leukemia function, its function relates to the fact that radiate dosage size and radiation position. It is once heavier dose of (1- 9Gy) Send to leukemia function while being low dose of many times.
Unless all over with radiating shine by getting bigger one, especially bone marrow is shine, can't can cause by bone marrow so that and immunity so that, can still observe fracture and recombination of the chromosome in several months after shining. The radioactive rays can cause the reversible fracture of bifilar DNA, thus cause tumour and virus to duplicate and discharge in cells. It is not lymphocyte leukemia and chronic grains of cell leukemia that can bring out to radiate urgently, chronically, but not seen chronic lymphocyte leukemia, and often a section of bone marrow inhibits one before having illness coming on, it incubation period was about 2- 16.
(4)Chemical factor
The function of causing leukemia of benzene is more definite. Benzene causes acute leukemia to take acute grains of cell leukemia and red leukemia as the core. Alkanisation pharmaceutical and the intersection of cell and malicious medicine can cause, continue even relatively definite leukemia of taking place etc., majority continue person who take place leukemia to take place in original lymphocytic the intersection of system and malignant tumour and apt to produce immune malignant tumour of defect, take place after long-term alkanisation pharmaceutical treatment, incident even after breast cancer, ovarian cancer and lung cancer chemotherapy to continue taking place leukemia.
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