The follow-up tests performed show the typical dynamics of a primary CMV infection with a loss of p150 rec IgM reactivity (IgM index <1,0), a steep increase in CMV IgG (about 4-fold), and the emergence of gB2-IgG, which indicates CMV neutralising antibodies (Table 1, Fig. 2, Additional file 1). The gene discussed is CD40LG; the disease is cytomegalovirus infection.