Upon closer investigation, s allele carriers, but not l/l genotype carriers, possessed significantly increased methylation of CpG islands flanked upstream by the 5-HTTLPR and downstream by the untranslated first SLC6A4 exon, which showed increased methylation levels as a function of recent chronic daily stress and correlated positively with glucocorticoid receptor (NR3C1) expression [for more evidence of NR3C1 as a key mediator of early adversity in stress-related disorders, please refer to Palma-Gudiel, Cordova-Palomera (23)]. Here, NR3C1 is linked to stress-related disorder.