title: Blood levels of folate at birth and risk of childhood leukemia.
abstract: BACKGROUND
  A role for folate in cancer etiology has long been suspected because of folate's function as a cofactor in DNA methylation and maintenance of DNA synthesis. Previous case-control studies examining the association between risk of childhood acute lymphoblastic leukemia (ALL) and mothers' self-reported folate intake and supplementation have been inconclusive.
  
  
  METHODS
  We used a quantitative microbiologic assay to measure newborn folate concentrations in archived dried bloodspots collected at birth from 313 incident ALL cases, 44 incident acute myeloid leukemia (AML) cases, and 405 matched population-based controls.
  
  
  RESULTS
  Overall, we found no difference in hemoglobin-normalized newborn folate concentrations (HbFol, nmol/g) between ALL cases and controls (2.76 vs. 2.77, P = 0.97) or between AML cases and controls (2.93 vs. 2.76, P = 0.32). Null results persisted after stratification by both birth period (1982-94, 1995-98, and 1999-2002) to account for the start of folate fortification of grain products in the United States, and by self-reported maternal prepregnancy supplement use. Similarly, no association was observed for major ALL subgroups.
  
  
  CONCLUSIONS
  Our results do not support an association between birth folate concentrations and risk of childhood AML or major ALL subgroups.
  
  
  CONCLUSIONS
  However, they do not rule out a role for folate through exposures after birth or in early stages of fetal development.
authors.affiliation: UC Berkeley School of Public Health, 1995 University Ave, Ste 460, Berkeley CA 94704, USA. anandc@berkeley.edu
authors.forename: Anand P
authors.initials: AP
authors.lastname: Chokkalingam
authors.forename: Danielle S
authors.initials: DS
authors.lastname: Chun
authors.forename: Emily J
authors.initials: EJ
authors.lastname: Noonan
authors.forename: Christine M
authors.initials: CM
authors.lastname: Pfeiffer
authors.forename: Mindy
authors.initials: M
authors.lastname: Zhang
authors.forename: Stacy R
authors.initials: SR
authors.lastname: Month
authors.forename: Denah R
authors.initials: DR
authors.lastname: Taggart
authors.forename: Joseph L
authors.initials: JL
authors.lastname: Wiemels
authors.forename: Catherine
authors.initials: C
authors.lastname: Metayer
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Buffler
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015470:Leukemia, Myeloid, Acute / Q000097:blood / Q000209:etiology*; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000097:blood / Q000209:etiology*; D011379:Prognosis; D013997:Time Factors
chemical_list: D005492:Folic Acid