How many human genes are there? That question began Thursday night’s “Science Café” at Fido in Hillsboro Village.
“Genetics Today” was the subject of the free scientific exploration, sponsored at the popular eatery and coffee house every third Thursday by Nashville’s Adventure Science Center.
The speaker, Jonathan Haines, who directs the Vanderbilt Center for Human Genetics Research, was engaged and animated as he fielded questions from a small sampling of the general public April 21.
Casually dressed with his sleeves rolled above his elbows, his hands constantly in motion to punctuate his points, the scientist took on a wide range of queries:
- What portion of the modern human genome comes from Neanderthals?
- What are the risks of genetic engineering?
- Can my genetic information be used to deny me health insurance?
The session began with a half dozen people but quickly doubled in size, as those who apparently had come to Fido for a snack or to study with a cup of coffee scooted their chairs closer and began listening intently to the exchange of ideas.
Science cafés are springing up all around the country as scientists and members of the public realize that they can learn a lot from each other.
In Haines’ case, it gave him a chance to tell people what is most exciting about his work. “We’ve identified a lot of new genes that we didn’t know about that are involved in disease,” he said.
“What you live for is that ‘Aha’ moment when you discover something that’s really cool. Most of the time when you find something interesting, you spend the next year trying to prove yourself wrong . . . If you can’t do that, you start to believe that it’s real.”
As for the first question, there are 20,000 to 25,000 genes in the human genome.
The Neanderthal question referred to a report last year that sections of DNA appear to be shared between modern humans and Neanderthals, suggesting that Homo sapiens intermingled with their now-extinct cousins tens of thousands of years ago.
Haines responded that this early data needs to be approached with a healthy dose of skepticism. He pointed out that the Neanderthal samples were extracted from excavated, prehistoric bone fragments. “DNA is a stable molecule but it’s not perfectly stable,” he said. “It’s also very easy to contaminate.”
In response to the next question, Haines said, “We’ve been dealing with genetic engineering of plants and animals for thousands of years” through selective mating to yield desired traits, for example. “Now we’re doing it in the lab and a lot faster.”
Genetic engineering is very carefully regulated and controlled, noted one of his Vanderbilt colleagues, Dana Crawford, who participated in the discussion. But “any time you do something that’s never been done before,” Haines said, “you never quite know what the reaction is going to be.”
As for the privacy question, Haines pointed out that genetic information collected as part of a research study is carefully protected. However, he said, “your health records are not nearly as well protected. If your genetic information is in your health record, the insurance company can get it.”
A federal law prohibits discrimination, including denial of health coverage, based on genetic information. “There are a lot of holes in the law,” Haines said, “but it’s a first step.”