An intriguing look at our reproductive future.
Previously a researcher in cancer genetics at Imperial College London, Prasad switched careers to become a science writer and is frequently seen on British TV. The author suggests that with the rise of male and female infertility, the use of artificial methods to promote human reproduction will not only be possible, but necessary if the world population declines precipitously. Today, many women postpone childbirth until their mid-30s, when they are less fertile. Prasad also explains that the number of genes in the male Y chromosome has markedly decreased over the span of the human species (from 1,400 to 45 genes). While the female X chromosome is one of a pair (allowing an exchange of genetic material), the Y chromosome is a stand-alone without that possibility. As a consequence—and because sperm are created in abundance—they are more vulnerable to mutation. This may have negative consequences, but in the author's view, sperm mutations have also furthered evolution through natural selection. In the future, she writes, genetic engineering may allow both men and women to produce viable embryos from their own genome. Fetuses might then be provided with an artificial placenta and placed in an artificial womb. While these new advances are still not fully viable and, as the author notes, may raise ethical questions and promote moral dilemmas, there can be immediate benefits from this research—e.g., providing a more nurturing environment for premature babies than the incubators currently in use and allowing women with a damaged uterus or nonfunctional ovaries to give birth.
A fascinating examination of a future that may not be too distant, as well as an account of historical misconceptions about conception.