The results demostrated that metabolism of xenobiotics by cytochrome P450 (P = 9.06E−02), intestinal immune network for IgA production (P = 2.24E−08) and systemic lupus erythematosus (P = 5.81E−07) were the predominant KEGG pathways for genes in cluster 1, 3 and 4, respectively. Here, CD79A is linked to systemic lupus erythematosus.