Which of the following does not predispose to leukemia

Leukemia risk factors 1) General Gender: Men are more likely to develop CML, CLL and AML than women. Age: The risk of most leukemias, with the exception of ALL, typically increases with age. 2) Genetics Family history: First-degree relatives of CLL patients, or having an identical twin who has or had AML or ALL, increases the risk for developing the disease. Genetic diseases: AML has been associated with Down syndrome, Klinefelter syndrome, Patau syndrome, Fanconi anemia, Bloom syndrome, Ataxia telangiectasia, and Kostmann syndrome, may play a role in the development of leukemia. 3) Smoking Smoking cigarettes does increase the risk of developing AML 4) Exposures Radiation : Exposure to high-energy radiation (e.g., atomic bomb explosions) and intense exposure to low- energy radiation from electromagnetic fields (e.g., power lines). Chemical exposure: Long-term exposure to chemicals like benzene & ethylene oxide is considered to be a risk for leukemia. Drugs - alkylating agents & topoisomerase II inhibitors increase the risk of AML. 5) Previous Cancer Treatment Certain types of chemotherapy and radiation therapy for other cancers are considered leukemia risk factors.