单项选择题
Instead of advancing the public
discussion of biotechnology, David Shenk succeeds merely in displaying his
general ignorance and unfounded fears in his recent article "Biocapitalism" His
claim that "no living creature has ever before been able to upgrade its own
operating system" ignores transduction ( the act or process of transferring
genetic material or characteristics from one bacterial cell to another) and
bacterial conjugation (the temporary union of two bacterial cells), which are
ways organisms have "upgraded" their own genomes with novel DNA for hundreds of
millions of years. A first-year biology major could have told him that. For
Shenk to suggest that his daughter may someday use a before-birth genetic test
for "quick-wittedness" is extremely dun-witted, ignoring the complexity of
polygenetic traits while embracing a shallow genetic determinism. Nurture
——utterly absent from his discussion ——really does matter. Finally, worrying about the effects on the gene pool of a "culture in which millions choose the same desirable genes" is worse than pointless. The United Nations projects an approximate human population of eight billion by the year 2020. Even if Shenk’s worst fears are realized, and the wealthy parents of 100 million children can and do select for a polygenetic trait ——say, blue eyes ——this would present only a modest shift in the gene pool of 1 in 80, or 1.25 percent, assuming that none of those children would otherwise have been born with blue eyes. But what truly matters for the gene pool in the 1000-year-long run is the capacity of this trait to grant reproductive success in subsequent generations. Whatever advantage blue eyes currently grant in acquiring a mate presumably derives in part from the trait’s relative scarcity. Elementary economics shows that if you flood the market with an asset, you diminish the relative value of that asset: more blue eyes will make blue eyes less sexy. Is it really too much to expect familiarity with either biology or economics from an essay entitled "Biocapitalism" |