title: Association between breast cancer risk and the wild-type allele of human ABC transporter ABCC11.
abstract: BACKGROUND
  International mortality and frequency rates for breast cancer have been associated with the wet type of human earwax. It was recently found that earwax type is determined by a single nucleotide polymorphism (SNP), 538G>A (Gly180Arg), in ABCC11. The G allele determines the wet type of earwax as a Mendelian trait with a dominant phenotype. The present study examined the association between the frequency rate of breast cancer and the frequency of the G allele of ABCC11.
  
  
  METHODS
  Using blood samples from patients with invasive breast cancer (n = 270) and control volunteers (n = 273), the 538G>A SNP in ABCC11 was genotyped using the SmartAmp method.
  
  
  RESULTS
  The frequency of the G allele in breast cancer patients was higher than that in healthy controls. The odds ratio for the genotypes (G/G+G/A) to develop breast cancer was estimated to be 1.63 (p-value = 0.026), suggesting that the G allele in ABCC11 is associated with breast cancer risk.
  
  
  CONCLUSIONS
  This study showed that Japanese women with wet earwax have a higher relative risk of developing breast cancer than those with dry earwax. The ABCC11 SNPs that determine these phenotypes should be further investigated in order to obtain insights into the mechanisms by which breast cancer develops and progresses.
authors.affiliation: Department of Gastroenterological Surgery, Yokohama City University Graduate School of Medicine, Yokohama City University Medical Center, Yokohama, Japan.
authors.forename: Ikuko
authors.initials: I
authors.lastname: Ota
authors.forename: Aki
authors.initials: A
authors.lastname: Sakurai
authors.forename: Yu
authors.initials: Y
authors.lastname: Toyoda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Morita
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sasaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Chishima
authors.forename: Minoru
authors.initials: M
authors.lastname: Yamakado
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawai
authors.forename: Takefumi
authors.initials: T
authors.lastname: Ishidao
authors.forename: Alexander
authors.initials: A
authors.lastname: Lezhava
authors.forename: Koh-Ichiro
authors.initials: K
authors.lastname: Yoshiura
authors.forename: Shinji
authors.initials: S
authors.lastname: Togo
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Hayashizaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Itaru
authors.initials: I
authors.lastname: Endo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shimada
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000483:Alleles; D001943:Breast Neoplasms / Q000097:blood / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide
chemical_list: C435500:ABCC11 protein, human; D018528:ATP-Binding Cassette Transporters