More recently, the ratio between C-X-C chemokine receptor type 4 (CXCR4)+ harmful and hyperactive neutrophils to CD62L+ senescent neutrophils and the levels of ROS in blood were found significantly higher in AD patients with severe dementia when compared to mild cognitive impairment (MCI) patients (100). The gene discussed is CXCR4; the disease is Cognitive impairment.