“Most cancers are rare in people with Down syndrome, whose overall cancer mortality is below 10 percent of that in the general population.” Cancer researcher Judah, Folkman, MD, believes that they are benefiting from a gene that blocks angiogenesis, the development of blood vessels essential for cancer’s growth. A single extra chromosome is sufficient to significantly suppress an angiogenesis and tumor growth in mice (and human cells). Researchers are using iPS cells created from skin cells of a patient with Down syndrome and injecting them into mice; iPS cells tend to induce tumors (known as teratomas) when inserted into mice. Researchers observed budding blood vessels that never fully formed. People with Down syndrome have nearly double levels of endostatin (an anti-angiogenic compound) because of the extra copy on chromosome 21.