The response of NCF1Ψ/NCF1 gene expression ratio to macrophage differentiation. a) Pyrosequencing was carried out to measure the ratio of NCF1B, NCF1 and NCF1C copies in the genomic DNA of THP-1 and differentiated macrophages. b) RT-qPCR was performed to measure the NCF1Ψ/NCF1 gene expression level using primers that recognize the GT or GTGT containing transcripts from all three gene copies. Five independent experiments were performed in duplicates using both GAPDH and β-actin as a reference. P values are indicated. c) Pyrosequencing was carried out to measure the relative contributions of NCF1 and its pseudogenes to the GTGT or GT containing transcript pool during macrophage differentiation.