In particular, in PN cases, the activation of C4 and C2 seems to be mainly associated with the over-expression of the immunoglobulins (IGLV1-40, IGKV3-20, IGLV1-47, IGLC3 and JCHAIN genes), whereas in IMN, the activation of these factors appeared related to the up-regulation of one key gene, that is FCN2, whose abundance was also seen as significantly increased in the first more restrictive statistical analysis (FC = 1.7; padj-value  = 0.007) (Figure 3). This evidence concerns the gene FCN2 and poikiloderma with neutropenia.