Your genome, just a click away

In the 1997 science fiction thriller Gattaca, Ethan Hawke's character fights to make a life for himself in a world where pervasive genetic testing and manipulation has left the imperfect by the wayside. At the time, it was easy to dismiss the film as a futuristic flight of fancy, not an issue that people would be facing in the next 10 years. After all, the Humane Genome Initiative already had spent years trying to sequence a single man's DNA, and had years left to go.

But, as often happens in technology, the science of genomics followed a “hockey stick” curve. The initial breakthrough of a single sequenced genome required the development of new sequencing techniques, which have drastically reduced the cost and time required.

Currently, commercial services will deliver an entire sequenced genome in less than a month, and there is a concerted effort to reduce that price to under US$1,000. Meanwhile, several companies offer consumers the ability to get vast amounts of their genetic data for as little as $400. Personal genomics, so recently science fiction, is now a click away on the Internet. But while this information may offer new insights for individuals into their heritage and physical characteristics, the possibility of a Gattaca-like future suddenly doesn't seem so far-fetched.

The two best-known personal genomic services, 23andMe and deCODEme, both operated in essentially the same manner. After visiting their web site and paying for the testing ($1,000 for deCODEme, $400 for 23andMe), a kit is sent in the mail. The consumer either rubs a stick shaped like a large tongue depressor against the inside of their cheek, or provides a (somewhat voluminous) sample of their saliva. The kit is returned to the company, which then processes the sample.

After a few weeks, the customer's genetic data becomes available on the website. But what he gets is not his complete genetic sequence. Instead, he gains access to as much as a million of their Single Nucleotide Polymorphisms (SNPs). Human DNA is, on the whole, identical from person to person. It is in the small differences brought on by random mutations that all the differences we see between people occur. Many of these differences are a single letter chance in a portion of DNA, a G instead of a C, for example. Fortunately for the companies, these single letter changes are relative easy to detect, and there are now “Snip Chips” that can detect the values of hundreds of thousands of individual SNPs from a single sample at the same time.

In the 1997 science fiction thriller Gattaca, Ethan Hawke's character fights to make a life for himself in a world where pervasive genetic testing and manipulation has left the imperfect by the wayside. At the time, it was easy to dismiss the film as a futuristic flight of fancy, not an issue that people would be facing in the next 10 years. After all, the Humane Genome Initiative already had spent years trying to sequence a single man's DNA, and had years left to go.

But, as often happens in technology, the science of genomics followed a “hockey stick” curve. The initial breakthrough of a single sequenced genome required the development of new sequencing techniques, which have drastically reduced the cost and time required.

Currently, commercial services will deliver an entire sequenced genome in less than a month, and there is a concerted effort to reduce that price to under US$1,000. Meanwhile, several companies offer consumers the ability to get vast amounts of their genetic data for as little as $400. Personal genomics, so recently science fiction, is now a click away on the Internet. But while this information may offer new insights for individuals into their heritage and physical characteristics, the possibility of a Gattaca-like future suddenly doesn't seem so far-fetched.

The two best-known personal genomic services, 23andMe and deCODEme, both operated in essentially the same manner. After visiting their web site and paying for the testing ($1,000 for deCODEme, $400 for 23andMe), a kit is sent in the mail. The consumer either rubs a stick shaped like a large tongue depressor against the inside of their cheek, or provides a (somewhat voluminous) sample of their saliva. The kit is returned to the company, which then processes the sample.

After a few weeks, the customer's genetic data becomes available on the website. But what he gets is not his complete genetic sequence. Instead, he gains access to as much as a million of their Single Nucleotide Polymorphisms (SNPs). Human DNA is, on the whole, identical from person to person. It is in the small differences brought on by random mutations that all the differences we see between people occur. Many of these differences are a single letter chance in a portion of DNA, a G instead of a C, for example. Fortunately for the companies, these single letter changes are relative easy to detect, and there are now “Snip Chips” that can detect the values of hundreds of thousands of individual SNPs from a single sample at the same time.

However, the degree to which they may affect an individual may be very weak, explains David Magnus, PhD, Director of the Center for Biomedical Ethics at Stanford. “Most of the traits that we have information about, from say an array that looks at SNPs… in the vast majority of the traits, those are not very predictive. So even if you have a gene for Type 2 diabetes, or that is positively correlated with heart disease, or for being tall, it contributes so little casually, that it doesn't really tell you much about the likelihood of the actually phenotype.” This is in contrast to tests such as those for the BRAC1 and BRAC2 genes, which have a large probabilistic impact on the chances of a woman developing breast cancer. “Now [with the new tests] we're talking about things that have so little impact that it's just swamped by any number of other causal factors, including environmental ones.”

GINA To The Rescue?

While some see personal genomics as ushering in a new era of personalized health care, it also raises the specter of discrimination on the basis of genetic data. Conceivably, health insurance companies could start to consider a positive SNP test for a disease to be a pre-existing condition, for example. Or an employer might not hire someone who carried an increase risk of a mental illness, according to their genetic data. To answer some of these concerns, Congress passed GINA, the Genetic Information Nondiscrimination Act, in 2008.

But as Hsu points out, it's only a first step. “As it stands, it only applies to health insurance coverage and to employer discrimination based on genetic information. It doesn't currently apply to life insurance or long term care insurance, things that people's decisions might be effected by because of genetic information.” He also points out that GINA only deals with the approval or denial of health care coverage, leaving insurance companies and health plans free to charge higher premiums for those they deem risky.

The issue of employment discrimination is particularly complex, according to David Magnus. Imagine that a certain subgroup in the general population is likely to become ill in the presence of some pathogen which is otherwise well-tolerated by people. If there was a test for that variation, a company might very well want to screen potential employees for it, if the work environment would expose the employee to the pathogen. “But then that raises questions about who has the authority to make those decisions,” Magnus says. “Can you force that testing on people against their will? If they decided that they needed the job, that it was much better paying than any other job in town, could they decide that it's worth it to get exposed to the risk? These are all the kinds of concerns that people have been very worried about.”