Word: sperm
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...tightly coupled to reproduction as certain pro-family moralists like to think. Even in so-called primitive hunter-gatherer societies, such as that of the Australian Aborigines, women have always managed to invent forms of contraception--herbal drinks, pessaries to block the cervix, oils to bog down the sperm. Then there is homosexuality, a reproductively senseless but nevertheless deeply compelling sexual strategy for millions of both sexes. Not to mention masturbation, celebrated by rapper Foxy Brown's chart-topping song Ill Na Na, in which she promises to "hold my own like Pee Wee in a movie theater...
...livestock, researchers at the Genetics & IVF Institute in Fairfax took advantage of a simple rule of biology: girls have two X chromosomes, while boys have one X and one Y. The mother has only Xs to offer, so the balance of power lies with the father--specifically with his sperm, which brings either an X or a Y to the fertilization party...
...happens, Y chromosomes have slightly less DNA than Xs. So by staining the sperm's DNA with a nontoxic light-sensitive dye, the Virginia scientists were able to sort sperm by gender--with a high rate of success--before using them in artificial insemination. The first couple to use the technique was looking to escape a deadly disease known as X-linked hydrocephalus, or water on the brain, which almost always affects boys...
...there is a lot we do not know about the effects of cloning, especially in terms of aging. As we grow older, changes occur in our cells that reduce the number of times they can reproduce. This clock of age is reset by normal reproduction during the production of sperm and eggs; that is why children of each new generation have a full life span. It is not yet known whether aging is reversed during cloning or if the clone's natural life is shortened by the years its parent has already lived. Then there is the problem...
Though most forms of DNA manipulation are now effectively unregulated, one important potential goal remains blocked. Experiments aimed at learning how to insert functional genetic material into human germ cells--sperm and eggs--remain off limits to most of the world's scientists. No governmental body wants to take responsibility for initiating steps that might help redirect the course of future human evolution. These decisions reflect widespread concerns that we, as humans, may not have the wisdom to modify the most precious of all human treasures--our chromosomal "instruction books." Dare we be entrusted with improving upon the results...