By comparing transcriptome of thymoma with and without myasthenia gravis, we found that 5 genes (PNISR, CCL25, NBPF14, PIK3IP1 and RTCA) were upregulated more than 2-fold, and that more than 30 genes were downregulated more than 2-fold. The gene discussed is PIK3IP1; the disease is myasthenia gravis.