A model for @entity1778 proposes that characteristic chromosomal translocations can arise in utero and that for most cases a second hit occurring postnatally will be necessary. Possible causal mechanisms for @entity1778 are environmental factors such as ionizing radiation from x rays and inherited susceptibility from polymorphisms in DNA repair genes. We performed a case-control study of childhood @entity981 measuring reported postnatal x rays in 701 cases aged 0-14 y and in as many population-based controls matched on age and sex. In addition we performed a case-only study in 207 cases to evaluate the interaction between x ray exposure and polymorphisms in DNA repair genes. There was an increase in risk of @entity1778 with number of x rays: the adjusted odds ratio for two or more x rays vs. none was 1.48 (95% confidence interval: 1.11-1.97). That risk was slightly higher among @entity1 (odds ratio = 1.67). A polymorphism in the @entity6471 gene (ex 5) involved in the base excision repair system was suggestive of an increased risk among @entity1 and a reduced risk among @entity1 . @entity6756 (ex 8), a mismatch repair gene, was associated with reduction of risk among @entity1 . Results from the genetic data are still preliminary and must be interpreted with caution especially because of the relatively small number of genotyped cases. However, ionizing radiation from x rays as well as polymorphisms in DNA repair genes are plausible risk factors for @entity1778 and should be studied more.

Diagnostic x rays, DNA repair genes and childhood XXXX .

@entity1 :: ('9606', 'Species') :: ['boys', 'girls'] @entity6756 :: ('4292', 'Gene') :: ['HMLH1'] @entity981 :: ('MESH:D054198', 'Disease') :: ['acute lymphoblastic leukemia'] @entity6471 :: ('328', 'Gene') :: ['APE'] @entity1778 :: ('MESH:D007938', 'Disease') :: ['leukemias', 'leukemia', 'childhood leukemia']
@entity981 :: (MESH:D054198,Disease) :: ['acute lymphoblastic leukemia']
