The detection of proliferating microglia in AD correlates with the up-regulation of the transcription factor PU.1 and the mitogens colony-stimulating-factor-1 (CSF1) and interleukin-34 (IL-34), key components of the pathway regulating microglial proliferation (Gomez-Nicola and others 2013). The gene discussed is IL34; the disease is Alzheimer disease.