PIK3CA and immune system disorder: The PI3K pathway defects are known to result in immunodeficiency and immune dysregulation.[64] Overactive MAPK activity induces microglial malfunction and leads to locoregional demyelination and is a significant contributor to MS pathophysiology.[65] Fifty-nine MS risk genes participated in the hsa05152: Tuberculosis pathway, and were primarily the HLA-II, toll-like receptors, caspase family, BCL2 family, interleukin family, interferon family, and so on.