Since the United States Food and Drugs Administration (FDA) declined to approve tofacitinib for moderate-to-severe psoriasis, permitting it only to be used in psoriatic arthritis, reumatological arthritis and ulcerative colitis, due to additional safety analysis requirement [49,62,63,64,65], the interplay between JAK/STAT inhibitors and gut microbiome in psoriatic patients still remains unknown. The gene discussed is SOAT1; the disease is ulcerative colitis.