PORTLAND – When sisters Sarah Caldwell, 16, and Kathryn Caldwell, 13, first learned last year that their father, Jim Caldwell, had amyotrophic lateral sclerosis, an incurable disease, they wanted to keep the news from their friends.

Still reeling from their mother’s own fight with cancer that had begun two years earlier, the Falmouth sisters didn’t want people to pity them, said their mother, Sharon Leskanic. But the girls soon changed their minds in order to help find a cure for the fatal neurodegenerative disease, also known as Lou Gehrig’s disease, Leskanic said.

“They have come to understand the fragility of life and the strength of their friends and community,” said Leskanic.

On Saturday, thanks to Sarah’s organizational abilities, the Caldwell and Leskanic family was joined by more than 200 relatives and friends on the Walk to Defeat ALS, collectively raising nearly $17,000 for ALS research.

The Caldwell-Leskanic group was the largest team by far on the 3.5-mile walk from Payson Park around Back Cove in Portland. Amy Kuzma, director of the Northern New England Chapter of the ALS Association, which sponsored the event, said the walk, which included about 800 participants, is expected to raise $155,000 for ALS research and advocacy.

Kuzma said about 60 people in Maine and 30,000 nationally have ALS at any given time. The disease affects nerve cells in the brain and spinal cord and results in paralysis.

Research has tied the disease to a genetic mutation, but little else is known. ALS commonly strikes between the ages of 30 and 70. About 10 percent of the cases are inherited genetically.

Only one drug, which can prolong survival by several months, has been approved by the Food and Drug Administration to treat ALS.

Diagnosed a year ago, Jim Caldwell, 56, now needs a wheelchair and speaks slowly and softly. His friends and family say it’s been a painful year.

“The fact that it has hit Jim so quickly has made everyone lose their breath,” said Lisa Madden of Falmouth, a close family friend.

Flanked by his wife and daughters, Caldwell simultaneously smiled and cried as the team continued to grow before the start of the walk.

“I’m overwhelmed,” he said.

Beth Quimby can be contacted at 791-6363 or at:

bquimby@pressherald.com