FCRL5 and AIDS: Genome-wide screening has revealed that the entire 1q21-q23 region—which includes the FCRL5 gene—has been implicated in several AIDs; in subjects with high neurodegeneration, some changes in the peripheral blood mononuclear cells (PBMCs), including lower FCRL5 expression and higher peripheral blood B-cells activation status—characterized by a down-regulation of B-cell-specific genes—have been noted (13).