title: Quantitative trait locus mapping for ethanol teratogenesis in BXD recombinant inbred mice.
abstract: BACKGROUND
  Individual differences in susceptibility to the detrimental effects of prenatal ethanol (EtOH) exposure have been demonstrated. Many factors, including genetics, play a role in susceptibility and resistance. We have previously shown that C57BL/6J (B6) mice display a number of morphological malformations following an acute dose of EtOH in utero, while DBA/2J (D2) mice are relatively resistant. Here, we present the results of quantitative trait locus (QTL) mapping for EtOH teratogenesis in recombinant inbred strains derived from a cross between B6 and D2 (BXD RIs).
  
  
  METHODS
  Pregnant dams were intubated with either maltose-dextrin or 5.8 g/kg EtOH on day 9 of gestation (GD9). On GD 18, dams were sacrificed and fetuses and placentae were removed. Placentae and fetuses were weighed; fetuses were sexed and examined for gross morphological malformations. Fetuses were then either placed in Bouin's fixative for subsequent soft-tissue analyses or eviscerated and placed in EtOH for subsequent skeletal examinations. QTL mapping for maternal weight gain (MWG), prenatal mortality, fetal weight (FW) at c-section, placental weight (PW), and several morphological malformations was performed using WebQTL.
  
  
  RESULTS
  Heritability for our traits ranged from 0.06 for PW to 0.39 for MWG. We found suggestive QTLs mediating all phenotypes and significant QTLs for FW and digit and rib malformations. While most QTL regions are large, several intriguing candidate genes emerged based on polymorphisms between B6 and D2 and gene function.
  
  
  CONCLUSIONS
  In this first mapping study for EtOH teratogenesis, several QTLs were identified. Future studies will further characterize these regions. Identification of genes and epigenetic modifications mediating susceptibility to the teratogenic effects of alcohol in mice will provide targets to examine in human populations.
authors.affiliation: Institute for Behavioral Genetics, University of Colorado, Boulder, USA. cdowning@pharmacy.isu.edu
authors.forename: Chris
authors.initials: C
authors.lastname: Downing
authors.forename: Christina
authors.initials: C
authors.lastname: Balderrama-Durbin
authors.forename: Alexi
authors.initials: A
authors.lastname: Kimball
authors.forename: Jami
authors.initials: J
authors.lastname: Biers
authors.forename: Hali
authors.initials: H
authors.lastname: Wright
authors.forename: David
authors.initials: D
authors.lastname: Gilliam
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Johnson
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002492:Central Nervous System Depressants / Q000633:toxicity*; D002874:Chromosome Mapping; D000431:Ethanol / Q000633:toxicity*; D005260:Female; D005333:Fetus / Q000473:pathology; D005530:Foot Deformities / Q000139:chemically induced; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009929:Organ Size / Q000187:drug effects; D010920:Placenta / Q000187:drug effects; D011247:Pregnancy; D040641:Quantitative Trait Loci / Q000235:genetics* / Q000502:physiology; D013723:Teratogens; D015430:Weight Gain / Q000187:drug effects
chemical_list: D002492:Central Nervous System Depressants; D013723:Teratogens; D000431:Ethanol