Conversely, it has been speculated that higher estrogen levels (both exogenous and endogenous) may increase vitamin D binding protein (VDBP) levels [60], which in turn extend the half-life of vitamin D. To explore the association between genetic susceptibility to MS and vitamin D, the SNPs of 12 vitamin D-related genes have also been studied, but the results, often conflicting, have not been able to clarify this point [65]. The gene discussed is GC; the disease is myeloid sarcoma.