HAS3(Hyaluronan synthase 3) is a member of the NODC/HAS gene family. HAS3 is involved in the synthesis of the unbranched glycosaminoglycan hyaluronan, or hyaluronic acid, which is a major constituent of the extracellular matrix that contributes to tissue hydration, elasticity, and cellular signaling. Unlike HAS1 and HAS2, which produce high molecular weight HA, HAS3 generates lower molecular weight HA, which plays distinct roles in cellular processes. HAS3 expression is particularly important in the epidermis, where interferon-gamma significantly upregulates and transforming growth factor-beta downregulates HAS3, indicating involvement in inflammatory responses and tissue repair mechanisms.