title: Genetic and intermediate phenotypic susceptibility markers of gastric cancer in Hispanic Americans: a case-control study.
abstract: BACKGROUND
  Hispanics are the largest nonwhite ethnic group in the US population, and they have higher incidence and mortality rates for gastric cancer (GC) than whites and Asians. Studies have identified several genetic susceptibility loci and intermediate phenotypic biomarkers for GC in whites and Asians. No studies have evaluated genetic susceptibility and intermediate phenotypic biomarkers in Hispanics.
  
  
  METHODS
  In a case-control study of 132 Hispanic patients with GC (cases) and a control group of 125 Hispanics (controls), the authors evaluated the association of 5 single nucleotide polymorphisms (SNPs) that predispose whites and/or Asians to GC and of 2 intermediate phenotypic markers in peripheral blood leukocytes, ie, telomere length and mitochondrial DNA (mtDNA) copy number, with the GC risk.
  
  
  RESULTS
  The variant C allele of the reference SNP rs2294008 in the PSCA gene was associated with a significantly reduced risk of GC (per allele-adjusted odds ratio [aOR], 0.51; 95% confidence interval [CI], 0.33-0.77; P = .002). Leukocyte mtDNA copy numbers were significantly lower in GC cases (mean ± standard deviation, 0.91 ± 0.28) than in controls (1.29 ± 0.42; P < .001). When individuals were dichotomized into high and low mtDNA copy number groups based on the median mtDNA copy number value in the controls, those who had a low mtDNA copy number had a significantly increased risk of GC (aOR, 11.00; 95% CI, 4.79-25.23; P < .001) compared with those who had a high mtDNA copy number. Telomere length was not associated significantly with the risk of GC (aOR, 1.21; 95% CI, 0.65-2.27; P = .551).
  
  
  CONCLUSIONS
  Hispanics share certain genetic susceptibility loci and intermediate phenotypic GC biomarkers with whites and Asians and may also have distinct genetic susceptibility factors.
authors: Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, Texas; Department of Obstetrics and Gynecology, The First Affiliated Hospital of Harbin Medical University, Harbin, China.
authors: Yuhui
authors: Y
authors: Sun
authors: Jian
authors: J
authors: Gu
authors: Jaffer A
authors: JA
authors: Ajani
authors: David W
authors: DW
authors: Chang
authors: Xifeng
authors: X
authors: Wu
authors: John R
authors: JR
authors: Stroehlein
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000235:genetics; D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000235:genetics; D016022:Case-Control Studies; D056915:DNA Copy Number Variations; D004272:DNA, Mitochondrial; D005260:Female; D058851:GPI-Linked Proteins / Q000235:genetics; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D006630:Hispanic or Latino / Q000235:genetics*; D006801:Humans; D007962:Leukocytes; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000235:genetics; D009363:Neoplasm Proteins / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D016017:Odds Ratio; D010641:Phenotype; D054801:Phosphoinositide Phospholipase C / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D060888:Real-Time Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000235:genetics*; D016615:Telomere; D014157:Transcription Factors / Q000235:genetics; D014481:United States / Q000453:epidemiology
chemical_list: D000951:Antigens, Neoplasm; D004272:DNA, Mitochondrial; D058851:GPI-Linked Proteins; D005819:Genetic Markers; C060192:MUC1 protein, human; D018396:Mucin-1; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; C110843:PSCA protein, human; D014157:Transcription Factors; C427486:ZBTB20 protein, human; D055372:AMP-Activated Protein Kinases; C526180:PRKAA1 protein, human; D054801:Phosphoinositide Phospholipase C; C423320:phospholipase C epsilon
keywords: Hispanics; copy number; gastric cancer; mitochondrial DNA; single nucleotide polymorphism; telomere length