title: Vitamin D receptor biochemical and genetic profiling and HLA-class II genotyping among Lebanese with multiple sclerosis - A pilot study.
abstract: BACKGROUND
  Multiple sclerosis (MS) is an autoimmune demyelinating disease affecting mostly young adult females with multifactorial etiology. Recent studies suggested that adequate vitamin D levels may lower the risk of developing MS.
  
  
  OBJECTIVE
  Our aim was to explore the relationship between vitamin D receptor (VDR) polymorphism, HLA-DR locus genotype, and serum vitamins D and A levels in the Lebanese population.
  
  
  METHODS
  Fifty MS patients were recruited for this study. The control group consisted of 48 healthy and 51 patients with other neurological disorders (non-MS). Biochemical analysis included serum 25 hydroxyvitamin D (25OHD) and vitamin A. Molecular analysis targeted VDR genotypes (ApaI, TaqI and BsmI) and low resolution HLA typing for DRB1 locus.
  
  
  RESULTS
  Healthy and non-MS groups had comparable parameters and were combined into one control group. No significant differences were found between MS and control groups for VDR genotypes. The frequency of HLA-DRB1*15 was significantly higher in MS patients (22%) compared to controls (8%) (p=0.018). Odds ratio for MS in the presence of DRB1*15 allele was 3.21 (p=0.018). Cosegregation with A (ApaI) and b (BsmI) alleles did not influence the risk for MS. 25OHD levels were significantly higher in MS patients compared to controls (p=0.002), due to more frequent oral supplementation (p=0.005). Vitamin A levels were comparable between the two groups. When all parameters were included in a logistic regression model adjusted for supplementation, only HLA-DRB1*15 (OR=3.42; p=0.027) contributed significantly to MS risk.
  
  
  CONCLUSIONS
  There was no association between serum vitamin D or A or VDR genotypes and MS. HLA-DRB1*15 was the major factor imposing more than 3 folds greater risk for developing MS among Lebanese.
authors.affiliation: Multiple Sclerosis Center, Department of Neurology, American University of Beirut Medical Center, Lebanon.
authors.forename: Bassem
authors.initials: B
authors.lastname: Yamout
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Nathalie M
authors.initials: NM
authors.lastname: Karaky
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Rami A R
authors.initials: RAR
authors.lastname: Mahfouz
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Fadel
authors.initials: F
authors.lastname: Jaber
authors.affiliation: Department of Neurology, American University of Beirut Medical Center, Lebanon.
authors.forename: Nour
authors.initials: N
authors.lastname: Estaitieh
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Dina
authors.initials: D
authors.lastname: Shamaa
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Fatmeh
authors.initials: F
authors.lastname: Abbas
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon.
authors.forename: Rouba
authors.initials: R
authors.lastname: Hoteit
authors.affiliation: Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Lebanon. Electronic address: rd02@aub.edu.lb.
authors.forename: Rose T
authors.initials: RT
authors.lastname: Daher
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006684:HLA-DR Antigens / Q000235:genetics*; D006801:Humans; D007861:Lebanon; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood / Q000235:genetics*; D010865:Pilot Projects; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D018167:Receptors, Calcitriol / Q000235:genetics*; D018709:Statistics, Nonparametric; D014801:Vitamin A / Q000097:blood; D014807:Vitamin D / Q000097:blood; D055815:Young Adult
chemical_list: D006684:HLA-DR Antigens; D018167:Receptors, Calcitriol; D014801:Vitamin A; D014807:Vitamin D
keywords: 25 Hydroxyvitamin D; HLA-DRB; Multiple sclerosis; VDR gene; Vitamin A