We previously characterized the pleiotropic phenotype of double homozygous ptena-/-ptenb-/- embryos at different developmental stages [9], unveiled the formation of hemangiosarcomas in adult pten haploinsufficient zebrafish [44] and further studied the role of Pten in zebrafish angiogenesis [43] and hematopoiesis [45]. The gene discussed is PTEN; the disease is angiosarcoma.