At the site of M. leprae infection, some studies detected higher numbers of Tregs in lepromatous leprosy cutaneous lesions (Palermo et al., 2012; Bobosha et al., 2014; Saini et al., 2014), whereas others did not show any statistical differences in the expression of FOXP3 between the clinical forms (Massone et al., 2010; Parente et al., 2015). The gene discussed is FOXP3; the disease is leprosy.