The pressure decreases because there is less density meaning there are less atoms or molecules in a space. Gravity determines the density by pulling in more molecules towards â¦ the center of the Earth.
Therefore, about 85-90 percent of children with hereditary retinoblastoma develop multiple tumors that affect both eyes (bilateral disease). The remaining 10-15 percent of patients with hereditary retinoblastoma develop only a single eye tumor (unilateral disease).
But a baby with Tay-Sachs disease is born without one of those important enzymes, hexosaminidase A (HEXA). So, as those fatty proteins build up in the brain, they hurt the baby's sight, hearing, movement, and mental development. A child can only get Tay-Sachs by inheriting the gene for it from both parents. Tay-Sachs can be detected before birth, so couples who are thinking of having children may want to get a blood test to find out whether their child would be likely to have it. Who Is at Risk for Tay-Sachs? Each year, about 16 cases of Tay-Sachs are diagnosed in the United States.