Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

gradually wear off.
    Originally, the demand for test tube babies was enormous, given the legions of infertile couples. But who will clone a human? Perhaps parents mourning the death of a child. Or, more likely, a wealthy, elderly man on his deathbed who has no heirs—or no heirs he particularly cares for—and wants to will all his money to himself as a child, in order to start all over again.
    So in the future, although there might be laws passed preventing it, human clones will probably exist. However, they will represent only a tiny fraction of the human race and the social consequences will be quite small.
    GENE THERAPY
    Francis Collins, the current director of the National Institutes of Health and the man who led the government’s historic Human Genome Project, told me that “all of us have about a half-dozen genes which are prettyscrewed up.” In the ancient past, we simply had to suffer from these often lethal genetic defects. In the future, he told me, we will cure many of them via gene therapy.
    Genetic diseases have haunted humanity since the dawn of history, and at key moments may actually have influenced the course of history. For example, because of inbreeding among the royal families of Europe, genetic diseases have plagued generations of nobility. George III of En gland, for example, most likely suffered from acute intermittent porphyria, which causes temporary bouts of insanity. Some historians have speculated that this aggravated his relationship with the colonies, prompting them to declare their independence from England in 1776.
    Queen Victoria was a carrier of the hemophilia gene, which causes uncontrolled bleeding. Because she had nine children, many of whom married into other royal houses of Europe, this spread the “royal disease” across the Continent. In Russia, Queen Victoria’s great-grandson Alexis, the son of Nicholas II, suffered from hemophilia, which could seemingly be temporarily controlled by the mystic Rasputin. This “mad monk” gained enough power to paralyze the Russian nobility, delay badly needed reforms, and, as some historians have speculated, help bring about the Bolshevik Revolution of 1917.
    But in the future, gene therapy may be able to cure many of the 5,000 known genetic diseases, such as cystic fibrosis (which afflicts northern Europeans), Tay-Sachs disease (which affects Eastern European Jews), and sickle cell anemia (which afflicts African Americans). In the near future, it should be possible to cure many genetic diseases that are caused by the mutation of a single gene.
    Gene therapy comes in two types: somatic and germ line.
    Somatic gene therapy involves fixing the broken genes of a single individual. The therapeutic value disappears when the individual dies. More controversial is germ-line gene therapy, in which one fixes the genes of the sex cells, so that the repaired gene can be passed on to the next generation, almost forever.
    Curing genetic disease follows a long but well-established route. First, one must find victims of a certain genetic disease and then painstakingly trace their family trees, going back many generations. By analyzing the genes of these individuals, one then tries to determine the precise location of the gene that may be damaged.
    Then one takes a healthy version of that gene, inserts it into a “vector” (usually a harmless virus), and then injects it into the patient. The virus quickly inserts the “good gene” into the cells of the patient, potentially curing the patient of this disease. By 2001, there were more than 500 gene therapy trials under way or under review throughout the world.
    However, progress has been slow and the results mixed. One problem is that the body often confuses this harmless virus, containing the “good gene,” with a dangerous virus and begins to attack it. This causes side effects that can negate the effect of the good gene. Another problem is that not enough of the virus inserts the good gene into its target cells correctly, so that the body cannot produce enough of the proper protein.
    Despite these complications, scientists in France announced in 2000 that they were able to cure children with severe combined immunodeficiency (SCID), who were born without a functioning immune system. Some SCID patients, like “David the bubble boy,” must live inside sterile plastic bubbles for the rest of their lives. Without an immune system, any illness could prove fatal. Genetic analyses of these