Of genes and greens

Of genes and greens

Daniel McCabe | When Rima Rozen worked on her PhD in the late 1970s, under the tutelage of McGill's Charles Scriver, one of Canada's true pioneers in genetics, the field was a far cry from what it is today.

Professor Rima Rozen

"It's been a tremendous revolution," Rozen says. "When I was starting, the first genes had just been cloned. Now we know the sequence for the entire genome."

Rozen herself has made a major contribution to what we know about genes.

Her research group was the first to isolate and clone one gene -- methylenetetrahydrofolate reductase (MTHFR) -- that plays a crucial role in the synthesis of the major circulatory form of folic acid.

That in itself might not sound too significant to a layman's ears, but a common mutation in the MTHFR gene -- which Rozen and her team also identified - can have disastrous consequences.

Approximately 10 to 12 percent of North Americans have two copies of this mutation. As a result, these people are at higher risk than most individuals for such disorders as spina bifida and heart disease if they aren't receiving a sufficient supply of folic acid.

In the case of spina bifida, a permanently disabling birth defect that affects more children than muscular dystrophy, multiple sclerosis and cystic fibrosis combined, Rozen and her team were the first to identify a genetic risk factor associated with the disorder in humans.

Her work has earned notice from colleagues around the world. She has won career salary awards from both the Medical Research Council and the Fonds de la recherche en santé du Québec.

Her research efforts have also earned her this year's Prix Léo-Pariseau for excellence in the biological and health sciences from the Association canadienne-française pour l'avancement des sciences.

Unlike some genetic discoveries that offer the promise of a therapeutic payoff miles down the road, Rozen's work points to concrete steps that people can take right away to improve their chances for staying healthy.

The key for people at risk because of MTHFR mutations is to receive a sufficient amount of folic acid through multivitamins or foods rich in folates, such as legumes, liver and green vegetables.

For instance, with heart disease, it's known that high levels of the amino acid homocysteine -- which is regulated by MTHFR -- are associated with an increased risk of heart disease. "Homocysteine has become the new cholesterol," Rozen says of its growing infamy.

Several current studies are expected to paint a more detailed picture of the links between homocysteine and heart disease in the next few years.

"What we know for certain right now is that if you give people folates, the homocysteine level goes down. Folic acid helps get rid of homocysteine," says Rozen.

With spina bifida, the connection between taking folic acid and warding off sickness is even more obvious. Spina bifida results from the failure of the spine to close properly during the first month of pregnancy and it can result in newborns afflicted with varying degrees of paralysis, bowel and bladder complications, and an accumulation of fluid in the brain.

"There is a very clear connection between folic acid and reducing the risk of spina bifida," says Rozen. She notes that medical guidelines strongly recommend that any woman in her childbearing years who is thinking at all about having children makes sure that she is taking her daily requirement of folic acid.

So should we all just load up on folic acid to be on the safe side? "I wouldn't recommend loading up on anything," Rozen replies. "Most good multivitamins contain the daily requirement. That's what we need. But about one-third of the elderly in the U.S. don't get the daily requirement."

Rozen wears a lot of hats. A professor in the Departments of Human Genetics, Pediatrics and Biology, Rozen is also the scientific director of pediatric research for the McGill University Health Centre and the deputy director of the MUHC's research institute.

She also set up and continues to head the Molecular Genetics Diagnostics Service of the Montreal Children's Hospital, a service that supplies people who are considering becoming parents, but whose kids might be at risk for serious genetic disorders, with the scientific information they need to properly assess their options.

And she still makes her way to her lab as often as she can.

Using research mice that have been genetically altered so as to be without MTHFR, Rozen's lab is studying the rodents to get a better understanding of what can go wrong as a result.

Although Rozen's previous work has identified much about MTHFR, she wants to dig deeper and get a more thorough sense of the biological mechanisms underlying the MTHFR/folic acid equation. She also wants to probe the links between MTHFR and colon cancer.

"We might uncover some new therapeutic strategies in the process," Rozen suggests.

As a geneticist who has seen her work have an impact on peoples' health, Rozen worries about the negative tone of some media coverage of her field.

"We shouldn't be afraid of genetic knowledge," she asserts.

"There are things we need to think about -- such as confidentiality. And we have to address those concerns very carefully. But we can't let that sidetrack us from the benefits that this type of research can provide to society. My work is one small example; this type of research can identify ways to help people stay healthy."

Her work isn't her only passion. Rozen is also a big-time Jeopardy buff -- she even appeared on the show years ago, winning one competition. "One of my biggest thrills," she admits.

She isn't too impressed by that new interloper on the gameshow scene, Who Wants to Be a Millionaire.

"Jeopardy tests you on a much wider range of subjects. With Who Wants to Be a Millionaire, there are a lot of really trivial questions that have to do with TV shows or movies."

As for the recent Canadian edition that starred Pamela Wallin: "A disappointment, frankly."

Rozen grimaced as Wallin mangled French terms such as "Mont Tremblant." "I was quite embarrassed as a Canadian that such a respected journalist couldn't pronounce a few French words properly."