Rare Forms of Vitamin D3-Binding Protein (DBP): Analytical Literature Review

The article presents an analysis of the published data on the structure and functions of vitamin D3-binding protein (DBP), which is controlled by a single gene with three clearly defined alleles Gc1-F, Gc1-S, and Gc2. The article presents information on various structural and functional variants of DBP, which are determined genetically and can undergo post-translational modification by glycosylation. One of the derivatives of vitamin D3-binding protein is its partially deglycosylated form, which exhibits properties of a specific activator of macrophages and is designated as the GcMAF factor. The article pays special attention to rare forms of DBP, detected by the isofocusing method. An assumption is made about the nature of rare forms of DBP and the mechanism of occurrence of changes underlying the appearance of these forms.