Discrimination and Revelation: Potential costs of losing genetic privacy

Some risks of genetic privacy violation seem scarier or more likely than others. Anyone who doesn’t live in fear of assassination by poison shouldn’t live in fear of assassination by genetically personalized bioweapons. People who aren’t celebrities or political figures shouldn’t worry about someone exposing their genome on the public stage. No one cares enough about the average person to go through the effort.

However, although your Alzheimer’s gene variant might not be standing in the way of presidential aspirations, it could prevent you from buying affordable insurance or receiving a job offer. The risk of discrimination in areas like employment and insurance is one of the most widely-held fears surrounding genetic information.

If a potential employer receives genetic test results as part of your background information or requires the tests as part of a routine physical exam, they could learn of a predisposition to Alzheimer’s. Depending on your age at the time of application, they might decide not to hire you because your working years could be limited. Alternatively, the employer might change the terms of your retirement plan or employee health insurance to cut their potential employee-benefits costs. If you’re buying your own insurance, a company might raise your premium or deny you coverage based on your genetic predisposition to disease. For completely deterministic genes, such as the mutation for Huntington’s disease, the likelihood of discrimination only increases.

Detailed in your genes is information that you might want to hide not only from employers and insurance companies, but also from co-workers, friends, family, or even yourself. Your genes reveal things like your ancestry, HIV status, and susceptibility to diseases like breast cancer, Parkinson’s, or Alzheimer’s. “If you have an Alzheimer’s variant, maybe people are going to make fun of you. How would you like to be in high school and be teased about what genetic variant you have?” asks Mark Gerstein, a biomedical informatics researcher at Yale who focuses on genetic privacy.

In 1993, scientists identified the causative mutation for the fatal, degenerative Huntington’s disease. Ever since then, the children of Huntington’s patients have had to choose whether to get tested for the mutation or live in ignorance. Many choose ignorance. If someone else sequenced one of these children’s genomes without consent, they’d take away that choice and put the child at risk of discrimination.

Greg Cox, a genetics researcher at the Jackson Laboratory in Bar Harbor, Maine, says the issue of non-consensual revelation has already surfaced in the context of much simpler and less-invasive genetic information. Cox says biology curricula that teach the simple genetics behind physical traits like dimples or hair color have disappeared from most elementary schools due to their potential to reveal non-paternity. For example, upon learning in class that the gene for brown eyes dominates the gene for blue eyes, a brown-eyed child might realize his or her blue-eyed parents aren’t quite telling the truth since neither of them could have passed on a gene for brown eyes. “Giving children that information gets tricky,” says Cox.

Unexpected ancestry revelations have already plagued the field of genetics for decades, and it doesn’t look like the problem is going anywhere. “You might look into your own genetic information and realize you’re not related to your father’s side of the family,” Cox explains. Adopted children, frustrated in their attempts to look up their birth parents, could use their own DNA to circumvent sealed records against their parents’ wishes.

Once someone’s genome has been sequenced — consensually or otherwise — evidence increasingly suggests that it’s impossible to keep that data anonymous. As early as 2013, scientists affiliated with MIT were able to uncover the surnames and probable identities of United States men whose supposedly “de-identified” genomes were included in public sequencing projects. Researchers plugged specific sequences from targets’ Y chromosomes into genealogy databases like Ysearch.org to find familial surnames; when combined with “de-identified” database metadata such as age and state of residence, those surnames allowed researchers to triangulate the identities of the targets. By relying only on publicly accessible databases to de-anonymize the genetic information, the researchers showed that anyone could do the same — no hacking or specialized access needed.

More recently, Yale’s Gerstein co-published a bioinformatics study with fellow researcher Arif Harmanci, who studies genetic privacy at the University of Austin, Texas. The study details how they were able to link de-identified data back to individuals to reveal sensitive health information. For example, even a fragment of a target’s DNA could reveal matching sequences in a cancer research database, thereby revealing the cancer status and other medical predispositions of the target — and their family.

The shared nature of genetic information sets genetic privacy apart from other kinds of privacy. If your bank account information is stolen, you could lose a lot of money, but the effects are mostly limited to you; at worst, they spread to those who depend on you financially. In contrast, your decisions about genetic privacy affect all of your genetic relatives: grandparents, parents, aunts, uncles, siblings, and especially children. Revealing your own genome also reveals bits and pieces of your relatives’ genomes, whether they like it or not. “It’s scary because DNA is a very durable molecule built to last thousands of years,” says Gerstein. “Fifty years from now, if that information is out there, it affects the next generation. We’ll be able to figure out a hell of a lot more from the genome than we can now.”

Risks shared among family members entered the spotlight in May 2017, when consumer protection lawyer John Winston published a blog post highlighting language in the terms and conditions for Ancestry.com’s DNA testing service. The terms and conditions stated that the genetic data that Ancestry.com collects may be used against “you or a genetic relative.” Scenarios they explicitly mention include unwanted identification by law enforcement agencies, along with healthcare and employment discrimination. Furthermore, Winston contended that certain wording gave Ancestry.com DNA ownership rights that persisted beyond subjects’ deaths, creating additional concern for potential descendants.

Ancestry.com updated the terms and conditions to exclude the perpetuity clause shortly after Winston published his post; however, the service’s informed consent documents still carry warnings about the consequences “you or a genetic relative” could face as a result of genetic data collection. Asked to comment for this article, Eric Heath, the company’s Chief Privacy Officer, explains: “To help our members understand the risks of sharing information with researchers, we point out the risks of sharing this information — even if the hurdles to re-identification are very high and hard to maliciously exploit.”

Even Carl Zimmer, a well-known science writer who rebelled against genetic privacy principles in 2016 by making his entire genome sequence publicly available, acknowledges that he probably would not have made his genome public if sequence analyses hadn’t revealed him to be a relatively healthy individual. “If it had turned out that I had some serious genetic issues and those were things I’d have to talk to my children about, I might well have been pretty private about it,” he says.

Zimmer also recognizes that genetic material poses unique privacy issues. The physical nature of genetic information means you can’t prevent others from having access to your genome. “My DNA is all over this cup,” says Zimmer, gesturing to his mocha. “We do have the technology now to get DNA off of a cup — not just a few fragments, but actually reconstructing the whole genome,” he acknowledges. Gerstein adds, “You’re shedding gargantuan amounts of molecules all the time. We could go sequence those. There’s little you can do to prevent it.”