In myasthenia gravis (MG), miR-146a is downregulated and negatively correlated with levels of messenger RNA (mRNA) such as interleukin-1 receptor-related kinase 1 (IRAK1), tumor necrosis factor (TNF) receptor-related factor 6 (TRAF6), and inducible T cell costimulator factor (ICOS). This evidence concerns the gene ICOS and myasthenia gravis.