Vitamin D receptor polymorphisms and 25-hydroxyvitamin D in a group of Sicilian multiple sclerosis patients

Multiple sclerosis (MS) is an auto-immunedisease whose etiology remains controversial. Both geneticand environmental factors are thought to be involved in therisk of developing the disease. The purpose of our studywas to assess the association of Vitamin D receptor (VDR)polymorphisms with MS and to investigate the interactionof these polymorphisms with vitamin D levels. A total of179 Sicilian subjects, including 104 MS patients and 75healthy controls, were studied. The most common VDRpolymorphisms (Fok-I, Bsm-I, Taq-I and Apa-I) weregenotyped by polymerase chain reaction (PCR) followedby restriction fragment length polymorphism (RFLP)analyses in both groups and serum 25-hydroxyvitamin D[25(OH)D] levels were determined in MS patients by highperformanceliquid chromatography (HPLC). The distributionof genotype and allele frequencies of the four VDRpolymorphisms did not differ significantly between MSpatients and healthy controls, and were unrelated to theforms and the course of MS. Low serum levels of 25(OH)Dwere observed in MS patients but no association wasobserved between VDR and 25(OH)D levels except forFok-I. Moreover, MS patients with FF and Ff genotype hada significantly lower serum levels of 25(OH)D comparedwith ff carriers (P.05 FF vs Ff and Ff vs ff). Ourfindings showed no association between VDR polymorphismsand risk of MS. Interestingly, F allele could confera genetic predisposition to lower 25(OH)D levels.