Google gives new gene mapping service a bit of spit and polish

Just in time for Christmas, the Silicon Valley startup 23andMe - the name refers to the number of pairs of chromosomes in human DNA - has begun offering a personal genotyping service. For a $1,000 (£483) fee, 23andMe will run a sample of your DNA through a specialised gene-reading microchip that is able to identify, the company says, "nearly 600,000 data points on your genome".

It then uploads your genetic information on to its website, where you can use various "web-based interactive tools" to explore your ancestral origins and your likelihood of contracting hereditary diseases. To provide 23andMe with a DNA sample, you have to send the firm a small test tube filled with saliva. That requirement at first struck me as distasteful, maybe even demeaning. To have one's earthly origin and destiny reduced to a vial of spit seems like an affront to human dignity.

But maybe I'm being too fussy. After all, primitive cultures have long viewed bodily fluids, and saliva in particular, as carriers of secrets about personal identity and vitality. The Cherokee tribe of what is now the southeastern United States considered saliva "a vital element", according to the anthropologist Charles Hudson. Spittle "was to the individual as water in creeks and rivers was to the world", he wrote in a book about Native American religion. "If one's saliva were spoiled, it was a serious matter."

All that 23andMe is doing is giving an information-age twist to this mystical tradition. It's using automated laboratories, supercomputers and the internet to translate ancient symbolism into a practical digital service. Once a spiritual totem, spit is now just another informational medium.

23andMe isn't the only company creating personal gene maps; deCODE Genetics, a biopharmaceutical business in Reykjavik, Iceland, offers a similar service called deCODEme. But 23andMe is worth special note because it has the might of Google behind it. The search engine giant was an early investor in the startup, and it has a personal connection as well: Google co-founder Sergey Brin is married to 23andMe co-founder Anne Wojcicki.

Google's involvement suggests that 23andMe probably has larger ambitions than just providing individuals with gene maps. As its online store of genetic information grows and as customers add personal information, the company could end up with a database of extraordinary value to pharmaceutical firms, medical researchers and insurance companies.

Sorted and analysed with Google's sophisticated data-crunching tools, the database could disclose hidden connections between genes, aptitudes and diseases. In a privacy statement on its site, the company acknowledges that it plans to grant outside groups access to its database, allowing them to search, "without knowing the identities of the individuals involved", for correlations between genetic variations and health conditions. That could well turn into a major business.

The company also says that it will give users "the ability to connect with other 23andMe customers through sharing features". 23andMe could evolve into a social network, a biotech version of MySpace or Facebook where people make connections not with friends but with people who share similar genetic traits. This, too, could provide the basis for a lucrative business. Given that 23andMe tracks its customers' movements with cookies, it may not be long before we see genetically targeted advertising.

If all this seems a little Brave New World, that shouldn't be a surprise. Breakthroughs in genetics, combined with advances in computing and networking, promise to reshape many of our assumptions about our health, our identity and even our fate. We'll face a series of difficult questions.

How much do we really want to know about the path of our eventual decay? Services such as those from 23andMe can provide many benefits, but they also promise to create anxiety and fear.

I would think twice before spitting into that vial.

· Nicholas Carr's new book, The Big Switch, will be published in January. He blogs at