Word: sperms
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Over the past few decades, medical improvements have made parenthood possible for millions of couples suffering from infertility. One of the main technological breakthroughs is in-vitro fertilization, which unites the sperm and egg in a test tube before implanting the embryo in the mother’s womb. The technology, however, comes at a high price. The procedure itself is expensive, but, more importantly, it can greatly increase the chance of seeing birth complications...
...Francis Delmonico, a Harvard University professor, told the Wall Street Journal in 2007. "It's the poor person who sells." But Matas disagrees, noting that compensating kidney donors is no different from sanctioning sales of other body parts. "People get paid to be surrogate mothers. People get paid for sperm and hair," he says. "People say, 'Oh, those are safe and replenishable, but egg donation and surrogacy are risky, and yet they're legal.'" A legal market for kidneys may still be a long way from being socially and politically palatable, but at least it would cut down on cases...
...cells allow researchers to witness the normal development of sperm for the first time. "In the human, sperm development is a very long process," Nayernia says. "It takes more than 15 years and is not an accessible system. With this system, we can now watch that development in three months...
That's how long it took Nayernia's team to nurture sperm from embryonic stem cells, using a special cocktail of growth factors, nutrients and retinoic acid, a derivative of vitamin A. It is worth noting that researchers could generate IVD sperm only from male embryos; when they tried using stem cells from a female embryo, they were unable to get sperm to mature past the spermatogonial stage. That suggests that genes located on the Y chromosome, which female cells do not contain, may be essential for triggering the maturation of the primitive sperm cell...
...unclear whether IVD sperm may eventually be able to fertilize an egg successfully - the ultimate measure of similarity between IVD sperm and normal sperm. (Nayernia is currently testing whether mouse eggs fertilized with IVD sperm can lead to a healthy animal.) If the researcher can generate human IVD sperm that look like normally developed sperm and can get the artificially created germ cells to fertilize an egg, then he can allow the resulting embryo to develop for 14 days - according to U.K. law, embryos created for research purposes must be destroyed at that point. "We would need to study that...