title: Parental smoking, CYP1A1 genetic polymorphisms and childhood leukemia (Québec, Canada).
abstract: OBJECTIVE
  To evaluate the effect of parental smoking on childhood acute lymphoblastic leukemia and to determine if it is modified by child genetic polymorphisms.
  
  
  METHODS
  We carried out a case-control study in Quebec, Canada, including 491 incident cases aged 0-9 years and as many healthy controls matched on age and sex. Each parent was interviewed separately with respect to smoking habits during and after pregnancy. In addition, we carried out a case-only substudy with 158 cases classified according to presence or absence of the alleles *2A, *2B, and *4 in the CYP1A1 gene.
  
  
  RESULTS
  There were small risk increases with maternal smoking during the later trimesters. Interaction odds ratios were increased (although often not significantly) for the CYP1A1*4 allele at high levels of maternal smoking in the last trimesters and at low level of paternal postnatal smoking, and decreased for the CYP1A1*2B allele. The latter appeared to confer a protective advantage at low levels for maternal prenatal smoking and at high levels for paternal postnatal smoking.
  
  
  CONCLUSIONS
  Reported smoking habits showed no association with leukemia; risks for genetic polymorphisms lacked precision but indicated that the effect of parental smoking could be modified by variant alleles in the CYP1A1 gene.
authors.affiliation: Joint Department of Epidemiology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada. cirivard@epid.lan.mcgill.ca
authors.forename: C
authors.initials: C
authors.lastname: Infante-Rivard
authors.forename: M
authors.initials: M
authors.lastname: Krajinovic
authors.forename: D
authors.initials: D
authors.lastname: Labuda
authors.forename: D
authors.initials: D
authors.lastname: Sinnett
mesh_terms: D000483:Alleles; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D005220:Fathers; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007223:Infant; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000201:enzymology / Q000209:etiology* / Q000235:genetics*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011792:Quebec / Q000453:epidemiology; D012907:Smoking / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects
chemical_list: D014028:Tobacco Smoke Pollution; D019363:Cytochrome P-450 CYP1A1