“…Familial and genetic factors for chronic myeloid leukemia include people with Down syndrome and the Philadelphia chromosome (Zeeb and Blettner, 1998), and similarly individuals who have a family history of acute or chronic lymphocytic leukemia carry an increased risk of developing these subtypes as well (Pui et al, 2008;Redaelli et al, 2005;Belson et al, 2007). There is a suggestion that smoking (Brownson et al, 1993;Kane et al, 1999;Liu et al, 2011), exposure to extremely low-frequency electric and magnetic fields (William and Meghan, 2008), obesity (Larsson and Wolk, 2008;Dobbins and Choi, 2013), and occupational exposures to pesticides (Buffler et al, 2005;N. R. Council, 2006;Polychronakis et al, 2013) may be associated with the incidence of leukemia, but the data are not sufficient to make any definitive conclusions.…”