In their paper, Suárez‐Calvet et al (2016) examined CSF levels of the soluble ectodomain of TREM2 (sTREM2) in individuals representing the spectrum of AD, from cognitively normal with no biomarker evidence of AD pathology to preclinical AD to mild cognitive impairment (MCI) to AD dementia. The gene discussed is TREM2; the disease is Alzheimer disease.