Vitamin D receptor biochemical and genetic profiling and HLA-class II genotyping among Lebanese with multiple sclerosis - A pilot study

J Neuroimmunol. 2016 Apr 15:293:59-64. doi: 10.1016/j.jneuroim.2016.02.008. Epub 2016 Feb 15.

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.

Objectives: 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.

Conclusion: 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.

Keywords: 25 Hydroxyvitamin D; HLA-DRB; Multiple sclerosis; VDR gene; Vitamin A.

MeSH terms

  • Adult
  • Aged
  • Female
  • Gene Frequency
  • Genetic Predisposition to Disease*
  • Genotype
  • HLA-DR Antigens / genetics*
  • Humans
  • Lebanon
  • Male
  • Middle Aged
  • Multiple Sclerosis / blood
  • Multiple Sclerosis / genetics*
  • Pilot Projects
  • Polymorphism, Single Nucleotide / genetics*
  • Receptors, Calcitriol / genetics*
  • Statistics, Nonparametric
  • Vitamin A / blood
  • Vitamin D / blood
  • Young Adult

Substances

  • HLA-DR Antigens
  • Receptors, Calcitriol
  • Vitamin A
  • Vitamin D