title: Genetic association of apolipoprotein E polymorphisms with inflammatory bowel disease.
abstract: OBJECTIVE
  To study the association of apolipoprotein E (APOE) polymorphisms with the susceptibility of inflammatory bowel disease (IBD) in Saudi patients.
  
  
  METHODS
  APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis (n = 84) or Crohn's disease (n = 94) and matched controls (n = 200) using polymerase chain reaction and reverse-hybridization techniques.
  
  
  RESULTS
  The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls (P < 0.05), suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD. On the contrary, the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls, suggesting a protective effect of APOE ε3 for IBD. The prevalence of the ε4 allele was also higher in the patient group compared to controls, suggesting that the ε4 allele may also increase the risk of IBD. Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset. No effect of gender or type of IBD (familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.
  
  
  CONCLUSIONS
  APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients, though further studies with a large-size population are warranted.
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Ebtissam Saleh
authors.initials: ES
authors.lastname: Al-Meghaiseeb
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Mulfi Mubarak
authors.initials: MM
authors.lastname: Al-Otaibi
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Abdulrahman
authors.initials: A
authors.lastname: Al-Robayan
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Reem
authors.initials: R
authors.lastname: Al-Amro
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Ahmd Saad
authors.initials: AS
authors.lastname: Al-Malki
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Misbahul
authors.initials: M
authors.lastname: Arfin
authors.affiliation: Ebtissam Saleh Al-Meghaiseeb, Mulfi Mubarak Al-Otaibi, Abdulrahman Al-Robayan, Reem Al-Amro, Ahmd Saad Al-Malki, Department of Gastroenterology, Prince Sultan Military Medical City, Riyadh 11159, Saudi Arabia.
authors.forename: Abdulrahman K
authors.initials: AK
authors.lastname: Al-Asmari
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D001057:Apolipoproteins E / Q000235:genetics*; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D003424:Crohn Disease / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011110:Polymorphism, Genetic; D012307:Risk Factors; D012529:Saudi Arabia / Q000453:epidemiology; D055815:Young Adult
chemical_list: D001057:Apolipoproteins E
keywords: Apolipoprotein E; Inflammatory bowel disease; Polymorphism; Saudi