Q. Part of Slatewiper involves an ancient retrovirus, inserted in our genes by a lethal infection tens or hundreds of thousands of years ago. Is there any scientific basis for something like that?

A. Yes. A lot of the introns in our genome,  the so-called "junk DNA, seems to be left-overs from retroviral infections. Retroviruses have the capability of inserting themselves into the chromosomes of infected cells. If those infected cells are sperm or eggs, then they may be passed along just like any other part of a chromosome.

Just recently, research published in Nature (Nature Neuroscience 7, 1021 - 1023 (01 Oct 2004) indicates that a protein in our bodies, syncytin, is a remnant of an ancient retrovirus that entered our genome as much as 20 million years ago. High levels of syncytin have been implicated in multiple sclerosis, a progressive neurological disease.

Q. That's interesting, but Slatewiper involves a retrovirus in the genome which can be activated on cue, triggering the lethal disease. That must be your thriller writer's imagination, correct?

A. Well, it was my imagination back in 1993 when I first wrote Slatewiper. However, since that time, evidence has mounted that this would be a viable way to produce a genetically engineered weapon. A November 2003 report from the U.S. Central Intelligence Agency, "The Darker Bioweapons Future" (caution, this is a CPU-hogging, browser-crashing .pdf file) warned against:

"[W]eaponized gene therapy vectors that effect permanent change in the victim’s genetic makeup; or a'“stealth” virus,' which could lie dormant inside the victim for an extended period before being triggered. For example, one panelist cited the possibility of a stealth virus attack that could cripple a large portion of people in their forties with severe arthritis, concealing its hostile origin and leaving a country with massive health and economic problems."

This report, issued a decade after I wrote Slatewiper, describes precisely the sort of double-edged sword I envisioned with gene therapy being turned against humanity.

Q. But surely the incredible degree of sophistication needed to engineer such a virus puts it far beyond the capabilities of terrorists.

A. That was the case when I wrote Slatewiper, and remained the case until a few years ago. However, the equipment is available for a song on eBay and the knowledge is globally available. Anyone who thinks this is not a real possibility either is in denial, or has not kept current with the widespread migration of knowledge and resources.

Indeed, people who say it can't happen sound exactly like the people who were saying my first novel, The Trinity Implosion (1977), was implausible because terrorists could never get their hands on nuclear weapons.

This is even more likely now that sophisticated gene production and manipulation equipment – sequencers, synthesizers, PCR amplifiers – are all available on eBay. There is a growing community of garage gene hackers who are the genetic equivalent of the homebrew computer clubs that sparked the personal computer revolution. For example: the first purchase for my own garage DNA lab was a Perkin Elmer PCR gene amplifier for which I paid $200. I barely missed the winning bid on a synthesizer which ultimately went for $525.

Q. Okay, but even if terrorists could get their hands on things, could they really target ethnic codes in people's genes? That seems far fetched.

Not only possible, but increasingly probable.

Among many voices, the United Nations and the British Medical Association have issued warnings to indicate they believe ethnic weapons are a real threat, tailor-made for terrorists and rogue governments.

"The spectre of new biological weapons made possible by the mapping of the human genome makes it more urgent than ever to prevent biotechnology research from being hijacked for evil purposes.” That and more can be found on the Web at: www.unesco.org/courier/1999_03/uk/ethique/txt1.htm.

The Red Cross has also issued a warning about ethnic weapons.

And as recently as June 2004, MSNBC reported that the possibility had grown far more likely.

Ethnic DNA testing is widely available today. For less than $400 people can determine their precise ethnic origins.

Obviously, as the ability to define DNA ethnicity becomes commonplace and moves into the mainstream of popular culture, it becomes easier to use the results for evil. You can bet the techniques needed to refine this knowledge into a weapon are already being secretly developed.