A higher resolution bright field image of a representative E17.5 Tm4sf1-heterozygous embryo that exhibited brain hemorrhage demonstrates a lack of integrity in the forebrain–forebrain (fb-fb) and forebrain–midbrain (fb-mb) junctions and an accumulation of blood around the third and fourth ventricles (Figure 4A(c)). The gene discussed is TM4SF1; the disease is intracranial hemorrhage.