Growing Hope for Children With Progeria

By Jasmine Brown and Joseph Diaz

When Lindsay Ratcliffe was born she looked just like any other healthy baby girl. Her father, Joe Ratcliffe, told ABC News' Barbara Walters that Lindsay looked beautiful.

"The first thing I did, I counted her fingers. I counted her toes. I'm like, ten fingers, ten toes - we're good," said Ratcliffe with a smile." But after four months, Lindsay had gained little weight, and her parents knew something was seriously wrong.

Watch the full story on a special edition of "20/20? Saturday at 8 p.m. ET

Lindsay was diagnosed with Progeria, a rare disease that causes children to age rapidly. They are born looking healthy, but by the age of two they start aging at eight to ten times the normal rate. Lindsay is 8 but is just 36 inches tall and weighs 20 pounds.

Read more about Lindsay and Progeria

Progeria is caused by a mutation in a gene called LMNA. Only around 100 children in the world have the condition. When Lindsay was diagnosed, there was no treatment or cure. The average life span of a child with Progeria is 13 years.

View a slideshow of Lindsay and her family

However, a clinical trial has shown that a drug developed to treat cancer seems to improve some symptoms of the disease.

Read ABC News' Medical Unit's report on the trial

This past week Lindsay and her family went to Boston Children's Hospital for her latest round of tests. Doctors discovered that since her last appointment two years ago, Lindsay had grown six centimeters and gained two pounds - growth that would have seemed incredible before the new drug.

"I'm very excited, and I just can't believe it's working!" Lindsay said.

Dr. Leslie Gordon, medical director of the Progeria Research Foundation, said: "This is the first time that we've been able to ask that question, Can Progeria be treated? And the answer is yes. Many aspects of Progeria, including aspects of the cardiovascular system, can be treated. And we're very, very hopeful."

CLICK HERE for more information about Progeria.

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