Would you want your government to know how smart you are, whether or not you have a gene for Alzheimer’s, and your sexual history?

During a visit to Manchester, U.K., a few days ago, I got to take a peek inside a nondescript warehouse in which the secret inner lives of a half-million Brits are about to be stored in a gigantic refrigerator. It was a cold day in northern England, with snow on the way as I drove with Tim Peakman, the executive director of UK Biobank, to the edge of this former megacity of the Industrial Revolution. Spruced up in recent years from a rusted relic of Britain’s former glory, the city is now transforming itself into one of Britain’s centers for life-sciences research.

Biobank’s headquarters sits in a town-suburb about 20 minutes from the city center (or “centre,” as they say in the United Kingdom). Part of a global project to collect molecular material and medical histories from large populations in order to study the genetics of disease, Biobank has selected thousands of volunteers to pony up details and samples of their blood and urine. Researchers can then extract genetic materials, proteins, and anything else that seems worthwhile and reference it against medical histories. The idea is to use large populations to better understand the genetics of, say, diabetes.

Later this year, touch-screen machines will be installed in centers throughout Britain and ask detailed questions about people’s health and lifestyle: diet, health, sexual practices, cognitive abilities, and so forth. These will be added to the Department of Health medical records already stored in computers. Unlike in the United States, where records are still mostly on paper in thousands of different forms in health centers, doctors’ offices, and the workplaces of insurance companies, Britain has digitized almost every person’s record.

The samples will sit in two sets of tubes that Peakman shows me: one in cold storage for access by researchers, another in a deep freeze that will hold on to the samples like a molecular time capsule to be studied in the future. “The samples are the equivalent of a snapshot of where these people are when they give their samples,” says Peakman, an earnest young molecular biologist with short-cropped hair who worked in the pharma industry and as a consultant before joining Biobank in 2004. “It will be fascinating to compare them to samples in the future.”

I imagine having samples from the poor textile workers who once toiled here: how would they compare with their descendents if we had their samples?

Peakman says that people were concerned about privacy issues at first, but that Brits seems largely okay with giving up their secret inner lives after an exhaustive process of education, discussion, and regulations designed to protect individuals from prying eyes. I suggest that this still seems ripe for 1984-style abuse should the government or those with access want to use the data against people. I’m also thinkingof Gattaca, the 1997 Andrew Niccol film in which people in the near future don’t make a move without checking their own DNA, and companies and society shun anyone with defective genes.

Peakman says protections are strong and that participants are volunteers. “They sign a consent form; they are very aware of what they are doing,” he says. There are safety and security measures in place to ensure that names are kept confidential from everyone, including researchers. (The brochure issued to potential participants explains all this.)

Peakman adds that medical science needs this sort of information in order to move forward with genetics. For common diseases, we need to understand what genetic profiles and environmental inputs are at work in lots of people, he explains.

I get it, I say, understanding the argument for science. But having had my own genes tested for the good of an article and a book I wrote a few years back called Masterminds, I still wonder if I’ll get a call one day from my insurance company asking me about that positive test for the stroke gene, or the one linked with high blood pressure. What if someone I work for, or my lover, would prefer someone without these genes?

What if … what if? The scenarios are troublesome to consider, though so far there has not been significant abuse of the medical records that exist now. This could change; even so, the promise of helping bring about the better treatment of disease is enticing. For now, we Americans are largely protected against any mass national effort to collect our genetic data thanks to our dysfunctional health-care system. Meanwhile, we can thank those 500,000 plucky Brits–and thousands more volunteers in places as far-flung as Estonia and Taiwan–who are volunteering to give up their secret lives to these genetic population studies and “biobanks” so that perhaps we can all benefit.

Biobank website.

Biobank information leaflet for potential participants.