In addition, multiple perivascular bleedings were observed in the brain parenchyma solely in JAM-C−/− C57BL/6 mice with a hydrocephalus but were absent in the brains of JAM-C−/− C57BL/6 mice without a hydrocephalus and in wild-type C57BL/6 mice (Figure 7). Here, JAM3 is linked to Hydrocephalus.