It is now possible to scour complete human genomes for the presence of disease-associated genes without revealing any genetic information not directly associated with the inquiry, say Stanford University researchers.

This “genome cloaking” technique, devised by biologists, computer scientists and cryptographers at the university, ameliorates many concerns about genomic privacy and potential discrimination based on an individual’s genome sequence.

Using the technique, the researchers were able to identify the responsible gene mutations in groups of patients with four rare diseases; pinpoint the likely culprit of a genetic disease in a baby by comparing his DNA with that of his parents; and determine which out of hundreds of patients at two individual medical centers with similar symptoms also shared gene mutations. They did this all while keeping 97 percent or more of the participants’ unique genetic information completely hidden from anyone other than the individuals themselves.

“We now have the tools in hand to make certain that genomic discrimination doesn’t happen,” said Gill Bejerano, PhD, associate professor of developmental biology, of pediatrics and of computer science. “There are ways to simultaneously share and protect this information. Now we can perform powerful genetic analyses while also completely protecting our participants’ privacy.”

Bejerano shares senior authorship of the research, which was published Aug. 18 in Science, with Dan Boneh, PhD, professor of computer science and of electrical engineering. Graduate students Karthik Jagadeesh and David Wu share lead authorship of the study.

Applying cryptography techniques

The researchers hope that routine implementation of their technique will help individuals overcome any qualms about privacy that may keep them from sharing their genome sequences. In particular, people may be concerned that DNA sequences or genetic variants currently unassociated with diseases may in the future be linked with as-yet-unidentified increases in risk.