Locus-specific regulation of HLA-A and HLA-B expression is not determined by nucleotide variation in the X2 box promoter element

HLA class I expression is controlled by several regulatory pathways. The X2 box is a crucial element of the SXY regulatory module, which controls the transactivation of HLA class I and β2-microglobulin and of HLA class II and their accessory genes.[1][1],[2][2] Critical in this class II