title: Association of VDR-gene variants with factors related to the metabolic syndrome, type 2 diabetes and vitamin D deficiency.
abstract: The prevalence of metabolic syndrome (MetS) is rising alarmingly in the Saudi Arabian population. This study was conducted to assess the association between vitamin D receptor (VDR) polymorphisms and genetic susceptibility to components of the metabolic syndrome, type 2 diabetes mellitus (T2DM), and vitamin D deficiency in the Saudi Arabian population. Five-hundred-seventy Saudi individuals (285 MetS and 285 controls) were enrolled in this cross-sectional study. TaqI, BsmI, ApaI and FokI single nucleotide polymorphisms (SNPs) of the VDR gene were genotyped. The CT genotype and allele T of BsmI were associated with lower HDL-C levels [OR 0.60 (0.37, 0.96), p=0.03] and obesity [OR 1.4 (1.0, 1.90), p=0.04], respectively. The CT genotype and the dominant model CT+TT of BsmI were associated with increased risk of diabetes [OR 1.7 (1.2, 2.4), p=0.007], and [OR 1.5 (1.1, 2.2), p=0.01], respectively. On the contrary, the CT and CT+CC genotypes of FokI exhibited an association with a reduced risk of diabetes [OR 0.70 (0.49, 0.99), p=0.05] and [OR 0.67 (0.48, 0.94), p=0.02], respectively. The allele C of FokI was associated with lower risk of developing T2DM [OR 0.73 (0.56, 0.95), p=0.02]. The prevalence of vitamin D deficiency was lower in subjects with the AC genotype of ApaI [OR, 0.34 (0.14, 0.80), p=0.01]. Components of the MetS such as obesity, low HDL and T2DM were associated with the VDR gene. FokI and BsmI have protective and facilitative effects on the risk for T2DM, while the ApaI genotype was associated with reduced vitamin D deficiency.
authors.affiliation: Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Saudi Arabia; Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Prince Mutaib Chair for Biomarkers of Osteoporosis, Biochemistry Department, King Saud University, Riyadh, Saudi Arabia. Electronic address: aldaghri2011@gmail.com.
authors.forename: Nasser M
authors.initials: NM
authors.lastname: Al-Daghri
authors.affiliation: Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Saudi Arabia; Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Prince Mutaib Chair for Biomarkers of Osteoporosis, Biochemistry Department, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Omar S
authors.initials: OS
authors.lastname: Al-Attas
authors.affiliation: Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Saudi Arabia; Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Clinical Pharmacy Department, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Khalid M
authors.initials: KM
authors.lastname: Alkharfy
authors.affiliation: Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Nasiruddin
authors.initials: N
authors.lastname: Khan
authors.affiliation: Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Prince Mutaib Chair for Biomarkers of Osteoporosis, Biochemistry Department, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Abdul Khader
authors.initials: AK
authors.lastname: Mohammed
authors.affiliation: Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Prince Mutaib Chair for Biomarkers of Osteoporosis, Biochemistry Department, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Vinodson
authors.affiliation: Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Mohammed Ghouse Ahmed
authors.initials: MG
authors.lastname: Ansari
authors.affiliation: School of Biological Sciences, Life Science Building 85, University of Southampton, Southampton SO17 1BJ, UK.
authors.forename: Amal
authors.initials: A
authors.lastname: Alenad
authors.affiliation: Center of Excellence in Biotechnology Research, King Saud University, Riyadh, Saudi Arabia; Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, Riyadh, Saudi Arabia; Prince Mutaib Chair for Biomarkers of Osteoporosis, Biochemistry Department, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Majed S
authors.initials: MS
authors.lastname: Alokail
mesh_terms: D000328:Adult; D018912:Arabs / Q000235:genetics; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008075:Lipoproteins, HDL / Q000097:blood / Q000235:genetics; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D009765:Obesity / Q000209:etiology / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D018167:Receptors, Calcitriol / Q000235:genetics*; D012529:Saudi Arabia; D014808:Vitamin D Deficiency / Q000235:genetics*
chemical_list: D008075:Lipoproteins, HDL; D018167:Receptors, Calcitriol; C579457:VDR protein, human
keywords: 25-Hydroxyvitamin D; Cardiovascular diseases; Haplotype; Obesity; Polymorphism