Background
It has been suggested that polymorphisms in the WT1 gene modulate the effect of IFN‐β treatment in multiple sclerosis (MS) through regulation of the relationship between IFN‐β and vitamin D.
Objective
To examine whether WT1 modulates the relationship between IFN‐β and vitamin D in a longitudinal study with repeated assessment of vitamin D before and after initiation of IFN‐β.
Methods
In a prospective study of 85 patients with relapsing remitting MS, 25‐hydroxyvitamin D was measured at month 0, 1, 3, 6, 7, 9, 12, 18 and 24. None of the patients used any immunomodulatory treatment at inclusion, and all started IFN‐β treatment at month 6.
Results
The mean concentrations of seasonally adjusted 25‐hydroxyvitamin increased slightly (3.1 ± 1.2 nmol/l, P = 0.008) after initiation of IFN‐β. The association between IFN‐β treatment and 25‐hydroxyvitamin D was similar in patients carrying any of the two alleles in the WT1 SNPs (rs10767935 and rs5030244) recently reported to modulate this relationship.
Conclusions
In this prospective study with repeated measurements of 25‐hydroxyvitamin D before and during treatment with IFN‐β, we did not find that genetic variation in WT1 plays any role in regulating the relationship between IFN‐β and serum 25‐hydroxyvitamin D.