To evaluate in more detail the pathological alterations accompanied by the development of the hydrocephalus in JAM-C−/− C57BL/6 mice we performed immunohistochemical stainings for glial fibrillary acidic protein (GFAP), comparing brains from JAM-C−/− C57BL/6 mice with a hydrocephalus score of 1 and 2 with wild-type brains. The gene discussed is GFAP; the disease is Hydrocephalus.