DNA Sequencing Will Become Affordable in Five Years – is It Indeed Such a Good News?

by Gopalan on Sep 23 2007 12:44 PM

One’s susceptibility to diseases could be said to be determined by one’s DNA blue print or the genome sequence.

Science is progressing at such a breathtaking pace the sequencing of 20,000 to 25,000 genes of an individual could become quite common and affordable, many believe. That way enough preventive measures could be taken is the positive side of it.

But on the other hand the possibility could have huge privacy, ethical and societal implications, says an article published in Thursday's issue of Science.

As part of a regular physical, you could one day get a printout of your genes, identifying anything from a high cancer risk to a genetic mutation that you could pass on to your children.

But while this critical information could one day lead to personalized health care, such as specific tailor-made drug therapies that target your genetic weaknesses, it also opens a Pandora's box of ethical and societal challenges, Timothy Caulfield, Canada research chair in health law and policy and one of the study's authors told Friday.

"The challenge presented by genome sequencing is that it's going to provide a huge amount of genomic information for individuals, and so much of that is going to be probabilistic."

Caulfield said that in individual testing, most genes that will be mapped aren't definite indicators for the onset of a certain disease. Rather, they will identify a predisposition toward a certain disease, increasing that individual's risk of contracting it. "So maybe you have a slightly increased risk towards heart disease, or perhaps obesity. But what does that really mean?" said Caulfield. And given that much of this sequencing will be "far in advance of preventive strategies," he said, what is the average individual to do with all of this information? Just because you've been told you're at genomic risk of disease, does that mean you're going to exercise and eat better? I think it would be quite overwhelming," said Caulfield. "We need to investigate that."

Mainstream genomic sequencing, said Caulfield, could lead to a nation of "worried well," people armed with health information they're unsure how to use and which causes them concern.

The other issue that arises is whether pregnant women will opt to screen the entire genome of their fetus to find out genetic abnormalities that may or may not have an impact on their unborn child's future quality of life — and whether they will terminate their pregnancies if scientists uncover "bad" genes.

"In Canada, we have the Assisted Reproduction Act, which can control what is screened prenatally," said Caulfield, adding that the legislation would rein in the screening process.

But pre-implantation genomic sequencing of embryos could be done, "and then you pick the profile you like best," he said.

Other issues could arise if that genomic information moves beyond the clinical domain, said Caulfield.

One is the accessibility of health insurance coverage, which some people fear could be denied if an individual's genetic information points to future health problems.

"I think that issue has been overplayed," said Caulfield, adding that "every state in the U.S. has anti-genetic discrimination laws. Through sequencing, he said, it will be uncovered that "we've all got bad genes. And they [insurers] need clients."

As well, thorny privacy issues may come into play. "It will not be long before companies are able to offer Facebook-like service centred around our genomes," says the article.

Caulfield said people are already publicly discussing their genetic makeups, a trend that could have societal ramifications down the road involving relationships and employment.

He cites a Facebook-like site,, where people can share personal stories about genetic diseases and genome sequencing.

"The medical community needs to consider the ways in which routine generation of this information will affect our health system and how this information might be used outside the medical context," says the article.

"Successful integration of personal genomics into routine clinical care will require clear standards, multidisciplinary collaboration and careful consideration of the ethical, social and clinical implications."