title: EED gene polymorphism in patients with colorectal cancer.
abstract: BACKGROUND
  Our previous work indicated that, first, the embryonic ectoderm development (EED) gene is a candidate gene associated with the pathogenesis of ulcerative colitis (UC) and, second, that the haplotypes of the EED polymorphism are one of the markers for UC susceptibility. The risk of developing colorectal cancer (CRC) increases in patients with inflammatory bowel disease.
  
  
  OBJECTIVE
  The present study aimed at determining the association between polymorphisms in the EED gene and CRC.
  
  
  METHODS
  Genotype analysis of EED single nucleotide polymorphisms (SNPs) was performed with high-resolution melting analysis, and the genotype and allele frequencies of the EED SNPs were compared between CRC patients and healthy controls. The haplotype frequencies of EED for multiple loci were estimated using the expectation maximization (EM) algorithm.
  
  
  RESULTS
  Our study had a power of 76.6% at a 0.05 significance level. Genotype and allele frequencies of the SNPs and haplotype frequencies of the EED gene in CRC patients were not significantly different from those in healthy controls. Only the allele frequency of g.-1850G>C in the rectal cancer (RC) patient group was significantly different from that of the control group (p=0.04). Similarly, the genotype and allelic frequencies of the EED SNPs for either tumor site (left or right) or tumor stage were not significantly different from those in healthy controls. However, our data show an association between the g.-993G>C polymorphism in the EED gene and the presence of lymph node metastasis in CRC.
  
  
  CONCLUSIONS
  These results suggest that the SNPs of the EED gene might not be associated with susceptibility to CRC. However, this study shows that the allele frequency of g.-1850G>C in the RC patient group was significantly different from that in the control group (p=0.04) and that g.-993G>C may play a role in the lymph node metastatic process of CRC.
authors.affiliation: Genome Research Center for Immune Disorders, Wonkwang University, Iksan, Chonbuk - South Korea and Digestive Disease Research Institute, Department of Internal Medicine, Wonkwang University, Iksan, Chonbuk - South Korea.
authors.forename: Geom Seog
authors.initials: GS
authors.lastname: Seo
authors.forename: Ji-In
authors.initials: JI
authors.lastname: Yu
authors.forename: Soo-Cheon
authors.initials: SC
authors.lastname: Chae
authors.forename: Won Cheol
authors.initials: WC
authors.lastname: Park
authors.forename: Sae Ron
authors.initials: SR
authors.lastname: Shin
authors.forename: Seung Taek
authors.initials: ST
authors.lastname: Yoo
authors.forename: Suck Chei
authors.initials: SC
authors.lastname: Choi
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Lee
mesh_terms: D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D063151:Polycomb Repressive Complex 2 / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide
chemical_list: C491488:EED protein, human; D063151:Polycomb Repressive Complex 2