title: Type 2 Diabetes Risk Allele Loci in the Qatari Population.
abstract: BACKGROUND
  The prevalence of type 2 diabetes (T2D) is increasing in the Middle East. However, the genetic risk factors for T2D in the Middle Eastern populations are not known, as the majority of studies of genetic risk for T2D are in Europeans and Asians.
  
  
  METHODS
  All subjects were ≥3 generation Qataris. Cases with T2D (n = 1,124) and controls (n = 590) were randomly recruited and assigned to the 3 known Qatari genetic subpopulations [Bedouin (Q1), Persian/South Asian (Q2) and African (Q3)]. Subjects underwent genotyping for 37 single nucleotide polymorphisms (SNPs) in 29 genes known to be associated with T2D in Europeans and/or Asian populations, and an additional 27 tag SNPs related to these susceptibility loci. Pre-study power analysis suggested that with the known incidence of T2D in adult Qataris (22%), the study population size would be sufficient to detect significant differences if the SNPs were risk factors among Qataris, assuming that the odds ratio (OR) for T2D SNPs in Qatari's is greater than or equal to the SNP with highest known OR in other populations.
  
  
  RESULTS
  Haplotype analysis demonstrated that Qatari haplotypes in the region of known T2D risk alleles in Q1 and Q2 genetic subpopulations were similar to European haplotypes. After Benjamini-Hochberg adjustment for multiple testing, only two SNPs (rs7903146 and rs4506565), both associated with transcription factor 7-like 2 (TCF7L2), achieved statistical significance in the whole study population. When T2D subjects and control subjects were assigned to the known 3 Qatari subpopulations, and analyzed individually and with the Q1 and Q2 genetic subpopulations combined, one of these SNPs (rs4506565) was also significant in the admixed group. No other SNPs associated with T2D in all Qataris or individual genetic subpopulations.
  
  
  CONCLUSIONS
  With the caveats of the power analysis, the European/Asian T2D SNPs do not contribute significantly to the high prevalence of T2D in the Qatari population, suggesting that the genetic risks for T2D are likely different in Qataris compared to Europeans and Asians.
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.|Division of Pulmonary and Critical Care Medicine, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: O'Beirne
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Salit
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Juan L
authors.initials: JL
authors.lastname: Rodriguez-Flores
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Staudt
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Charbel
authors.initials: C
authors.lastname: Abi Khalil
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.|Division of Translational Medicine, Sidra Medical Research Centre, Doha, Qatar.
authors.forename: Khalid A
authors.initials: KA
authors.lastname: Fakhro
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Amal
authors.initials: A
authors.lastname: Robay
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.|Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York, United States of America.
authors.forename: Monica D
authors.initials: MD
authors.lastname: Ramstetter
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Iman K
authors.initials: IK
authors.lastname: Al-Azwani
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Joel A
authors.initials: JA
authors.lastname: Malek
authors.affiliation: Department of Medicine, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Zirie
authors.affiliation: Department of Medicine, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Amin
authors.initials: A
authors.lastname: Jayyousi
authors.affiliation: Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Ramin
authors.initials: R
authors.lastname: Badii
authors.affiliation: Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Ajayeb
authors.initials: A
authors.lastname: Al-Nabet Al-Marri
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Chiuchiolo
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Alya
authors.initials: A
authors.lastname: Al-Shakaki
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Omar
authors.initials: O
authors.lastname: Chidiac
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Maey
authors.initials: M
authors.lastname: Gharbiah
authors.affiliation: Department of Medical Statistics and Epidemiology, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Abdulbari
authors.initials: A
authors.lastname: Bener
authors.affiliation: Department of Medicine, Weill Cornell Medical College-Qatar, Doha, Qatar.
authors.forename: Dora
authors.initials: D
authors.lastname: Stadler
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Neil R
authors.initials: NR
authors.lastname: Hackett
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.|Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, New York, United States of America.
authors.forename: Jason G
authors.initials: JG
authors.lastname: Mezey
authors.affiliation: Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America.|Division of Pulmonary and Critical Care Medicine, Department of Medicine, Weill Cornell Medical College, New York, New York, United States of America.
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Crystal
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D044466:Asian People; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology* / Q000235:genetics*; D005787:Gene Frequency; D016678:Genome; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011780:Qatar / Q000453:epidemiology; D012307:Risk Factors; D011795:Surveys and Questionnaires; D044465:White People