The Bcl-2 family gene BCL2 Antagonist/Killer 1 (BAK1) was found expressed at high levels in the apoptotic tissues of several clinical diseases (Zhou et al., 2008; Xu et al., 2011; Magee et al., 2014), and EM has been shown by some scholars to be a pathological consequence of inflammation and apoptosis (Laganà et al., 2019); thus, the high expression of BAK1 is involved in the pathomechanical process that regulates inflammation and apoptosis in the endometrium of EM patients. The gene discussed is BAK1; the disease is erythema multiforme.