Although the pathogenesis is still not fully understood, there is sufficient evidence to support the IgAN as an autoimmune disease, and a “four-hit hypothesis” (Hit 1, increased production and circulation of galactose-deficient [gd]-IgA1; Hit 2, antiglycan antibodies target gd-IgA1; Hit 3 and Hit 4, formation of immune complexes and mesangial deposition) has been proposed to explain the immune-related mechanism of IgAN [3, 4]. Here, IGHA1 is linked to autoimmune disease.