Tarah Sawler said she is happy she can help others.

Researchers at a Halifax university are targeting rare "orphan diseases" in a leading-edge study.

The Dalhousie University scientists are focusing on the extremely rare conditions because they tend to be neglected by research and pharmaceutical companies.

The $4.8 million project is called IGNITE, which stands for: identifying genes and novel therapeutics to enhance treatment.

Project leader Chris McMaster said the three-year study targets the genes that cause orphan diseases in the hope it can lead to new uses for existing drugs to treat the rare conditions.

"Rare is really not so rare. There are over 7,000 different orphan diseases and combined they affect one in 12 Canadians; 90 percent of these are life limiting," he said.

Orphan disease usually have no cure and limited treatment options. The genetic testing could also discover potentially troubling information for those afflicted.

"There are potential harms that come with that, including psychological burdens of knowing you might have a condition that doesn't have a treatment," said project leader Conrad Fernand.

Orphan disease takes sight

Those affected include 13-year-old Tarah Sawler. She was born with an orphan disease called Familial Exudative Vitreo-retinopathy, or FEVR.

The condition reduced her vision to about five per cent in one eye and gradually robbed her of her sight altogether.

"How sighted people learn everything that they do, I learned exactly like they did, except I learned different stuff. Like, for example, how when you're young you learn how to write, I learned how to read Braille," she said.

"I know it's hard for families to go through that kind of thing, and it just makes me feel so good to be able to help."

Her mother Cathy Sawler said FEVR runs on her side of the family, so she understood what was happening to her daughter.

"There's nothing they can do to stop it and you feel helpless, standing there watching your daughter lose her vision," she said.

"It's very hard for us because we had to go through it, but it's very satisfying to know that we can actually contribute."

The research comes too late for Tarah's sight, but the project could lead to prevention, treatment and cures for other families.