Recent reports have not really settled the point as to whether Humanin is produced by the Humanin gene, the nuclear mitochondrial DNA segment (NUMT) copies, or both, but have concentrated more on the actions of Humanin as a protective agent, especially in AD (Cohen et al., 2015; Hashimoto et al., 2013; Matsuoka, 2015; Tajima et al., 2002), as a retrograde signal peptide passing information about the mitochondrion to the rest of the cell (Lee et al., 2013) and as an agent improving cognition (Murakami et al., 2017; Wu et al., 2017). The gene discussed is MT-RNR2; the disease is Alzheimer disease.