In addition, there were 12 DEGs between CRS group and control group that clustered to the purine metabolism pathway of which expression was decreased for 2 genes, including Gucy2c and Entpd8, and increased for 10 genes, including Adcy7, Pde1a, Pde3b, Pde3a, Gucy1b1, Gucy1a1, Pde2a, Pde4d, Pde10a, Pde7b (Figures 6E, 7E, 8E). Here, PDE4D is linked to congenital rubella syndrome.