Association between Vitamin D receptor polymorphisms and Systemic Lupus Erythematosus in a Maltese cohort

Abstract

Systemic Lupus erythematosus (SLE) is autoimmune condition and presents itself with a variety of symptoms which makes it very challenging to diagnose. A variety of genes are said to be associated with SLE but one that would be focused on in this dissertation, is the Vitamin D Receptor gene (VDR). The VDR gene has 4 major polymorphisms, these include Bsm1, fok1, Apa1 and Taq1. The VDR controls the actions of vitamin D which is related to the modulation of the immune system. VDR can be found on immune cells. The association between SLE and VDR, is the low levels of vitamin D and compromised immune cells altering vitamin D management. This dissertation seeks to find the association between the VDR polymorphisms and SLE. Since allelic frequencies vary form country to another, in order to use such data, it has to be fabricated for the local allelic frequencies. Patients with SLE had to be recruited to carry out genotyping on. Once the data is gathered a range of statistical analysis is used to gauge the association between polymorphisms and SLE. It was found that when the Apa1 polymorphism is present as a homozygote for the variant allele (AA), there is a significant decrease in SLE prevalence. When the polymorphs were placed into haplotypes, the haplotype containing all wildtype alleles for VDR and haplotype containing all wild type with the variant for Fok1 had an increased prevalence of SLE by around a 2-fold increase. This data can be improved upon and used as a tool for SLE prediction.