IFIH1 and type 1 diabetes mellitus: Conversely, a rare genetic variant of the Interferon-Induced with Helicase C Domain 1 (IFIH1) gene, encoding a protein implicated in the host response to viruses and fungi [19], seems to be protective not only for type 1 diabetes and Ps, as demonstrated a few years ago [20], but also for PsA [21].