In healthy people, the circulating VDBP concentration seems to be independent of genetic or racial differences [19], age, adiposity [20], sunshine exposure [21], concentrations of VD sterols, and other hormones [22]; however, both 25OHD and VDBP are predominantly synthesized and secreted by the liver, and their circulating concentrations are impaired by hepatic disease [23, 24]. This evidence concerns the gene GC and liver disorder.