Scary as it is, eugenics can neither be wished nor willed away. It is being folded into our lives for a variety of reasons, and there is little governments can do to stop it even if they wanted to. PNS associate editor Walter Truett Anderson, a fellow of the Meridian International Institute, is a political scientist whose next book is entitled "Evolution Now: The Augmented Animal and the Whole Wired World."

Most Americans flinch when we hear the word "eugenics," conjuring images of Nazi scientists breeding an Aryan race. We'd be shocked to learn that eugenics has been practiced more in the United States than anywhere else in the world. And it's likely to become more, not less, important in the future.

The word eugenics -- from a Greek root meaning "well born" -- was coined in 1883 by Charles Galton, Charles Darwin's brilliant but erratic cousin. Galton wanted to improve on evolution by getting people to breed selectively so that the proportion of healthy, smart, capable and sane members of the human race would increase.

In England the idea gained instant popularity, embraced by right-wing Social Darwinists and left-wing Socialists alike. From there eugenics spread to the United States where, long before it was taken up by the Nazis in Germany, it went berserk. Feeding off American enthusiasm for progress and nativist fears that immigrants were polluting American gene pool, it spawned research centers such as the Race Betterment Foundation and laws requiring compulsory sterilization of criminals and mental patients, restrictions on immigrants, and bans on interracial marriage.

Today those laws have long since been repealed or declared unconstitutional. The research institutions are gone. Eugenics has been discredited as public policy and as science. No reputable scientists believe there is any clearly identifiable single-gene deficiency such as "feeblemindedness" or "criminality." The ancient argument about heredity vs. environment goes on as heatedly as ever, but even those who weigh in on the heredity side concede that personal characteristics have to be the product of many, many genes, interacting in ways not yet understood.

But meanwhile, genetic science has produced a list of diseases that are caused by a single -- and detectable -- gene. Some of these are painful, debilitating and usually fatal, such as Tay-Sachs syndrome, sickle-cell anemia, Huntington's chorea (the disease that killed folksinger Woody Guthrie) and cystic fibrosis. Acting on this information, more and more people are making decisions that are de facto eugenics. It is eugenics whenever a couple chooses to abort a defective fetus and try again; whenever a prospective parent makes a reproductive decision on the basis of knowledge that he or she carries genes for an inheritable disease; whenever a sperm bank screens prospective donors to find what traits they carry. If eugenics is about people-breeding, about attempting to improve the genetic heritage of those yet unborn, all these meet the definition. There may well be more real eugenics going on today than when it was popular.

Several years ago the New York Times ran a story, rich with historical irony, about a community of Orthodox Jews who have a program of genetic testing. Among Ashkenazi Jews, one person in 25 is a carrier of the Tay-Sachs gene, and one person in 25 is a carrier of the cystic fibrosis gene. When people with those genes marry, there is a one-in-four possibility in each pregnancy that a child will be born with the disease. Tay-Sachs is an incurable, fatal disease in which the child eventually becomes blind and paralyzed. Individuals with cystic fibrosis suffer with lifelong breathing and digestive problems, and about half of them die young.

So, every year, representatives of the Committee For Prevention of Jewish Genetic Diseases go to the Orthodox high schools and offer the students a blood test. Those tested are given an identification number, and it is registered at the program's central office. When a boy and a girl are being considered by the community's matchmakers as likely prospects to be united in marriage, the office reports either that the match is compatible, or that the young people both carry a recessive gene and would be likely to produce children with one of the diseases.

The people in the community call the program "Dor Yeshorim," Hebrew for "the generation of the righteous." "Today," a recent report states, "with continual testing, new cases of Tay-Sachs have been virtually eliminated from our community." The program is now being expanded to test for other diseases, including cystic fibrosis. But outside the community, some experts on medical ethics are publicly worried about it -- because, by any name, it is eugenics.

A lot of people would like eugenics to disappear. It's so easy to imagine ugly scenarios of new "master race" agendas, new assaults on human rights -- or, simply, of over-enthusiastic couples using scientific advice to create super-children.

On the other hand, it's not hard to imagine ugly scenarios connected with attempts to make it go away: self-appointed censors of scientific research, or police swooping down on the Jews of "Dor Yeshorim" and telling them they must go back to having children with Tay-Sachs.

Eugenics -- whether we call it that or not -- is here to stay. It is basically information which, once out in the world, tends to increase and circulate whether government approves or not. Eugenics becomes another one of the ever-growing class of things that ordinary people will learn about and fold into their lives, another set of choices they will make as the real arbiters, more than ever before, of their destinies.