OXTR and depressive symptom measurement: Estradiol increases the rate of transcription of the OXTR gene (116), resulting in elevations of oxytocin levels in the uterus (117) and in numerous brain regions (118) while heterozygosity for the OXTR rs2254298 polymorphism can interact with early life adversity to yield the highest levels of symptoms of depression, physical anxiety, and social anxiety (119).