Brooke Greenberg: 20-Year-Old "Toddler's" Legacy of Hope and Love

The Greenberg Family (Photo by Getty)The baffling case of Brooke Greenberg, a 20-year-old who never developed beyond the  toddler stage, may provide clues to help scientists unlock the secrets of longevity and fight age-related disorders, such as Alzheimer's, Parkinson's, and heart disease. Brooke, who passed away last Thursday, had the body and cognitive function of a 1-year-old. She didn't grow after the age of 5 — and basically, she stopped aging entirely.

"Brooke Greenberg, even after her sad passing, may help to reveal answers to one of the major mysteries in human biology: Why do we age and is there any way to slow or suspend the aging process?" Dr. Eric Schadt, director of the Icahn Institute for Genomics and Multiscale Biology at Mount Sinai Medical Center in New York, tells Yahoo Shine.

Brooke may have been the only person in the world suffering from a mysterious genetic disease that her doctors called Syndrome X. "Finding out that her DNA makeup is completely different than anyone else brought to our attention that we could help," her father, Howard Greenberg, told Yahoo Shine in a previous interview. "So eventually, at the end of the rainbow, there will be something that comes out of all this. I believe everyone is here for a reason."

More on Yahoo: Scientist Discovers Biological Clock That May Explore Aging

Brooke's growth was erratic in the womb. "One month she would be fine, one month she would just stop and play catchup," Brooke's mother, Melanie, told NBC Dateline. She was born a month prematurely, weighing only 4 pounds, and suffered from a rare form of hip dislocation that required surgery. Nevertheless, during her first year, Brooke's parents thought she would grow up and have a normal life. However, between ages 1 and 6, Brooke suffered a number of medical emergencies, including perforated stomach ulcers, a seizure, and a stroke — and she also stopped growing. Her parents consulted many specialists, but none could diagnose any endocrine or chromosomal abnormalities. Instead, doctors prescribed human growth hormone, which ultimately failed.

More Yahoo: Surreal Time Lapse Shows Effects of Aging

After Brooke's case caught Dr. Schadt's attention, his team began sequencing her DNA, looking for specific mutations related to her condition. He explained that by using stem cells taken from Brooke's skin, scientists can continue to study the special genes and other biological factors they identified, "seek to determine how they are involved in aging-related processes, and whether this new knowledge could help increase longevity and/or reduce aging-related disorders." He added, "Brooke’s contribution to human well-being ultimately could be a reduction in our overall disease burden — a gift to modern medicine and humanity.”

While Brooke's mysterious condition may lead to amazing scientific discoveries, on a quieter and more intimate level, she also leaves behind an inspiring legacy of unconditional love. "While the outside world may have noticed Brooke's physical stature and been puzzled by her unique development state, she brought joy and love to her family," Rabbi Andrew Busch, who spoke at her funeral on Sunday, told the Daily News. Throughout her life, her parents and three sisters cherished her and showered her with affection. She loved to be cuddled and tickled, and the Greenbergs said she developed a strong identity and a rebellious streak. When her younger sister, Carly, was born, she became jealous, like any other child would be, her parents said. And, despite the challenges the family faced over the years, their devotion never wavered. "The older she gets, it's unbelievable…everybody just wants to hold her," mother Melanie Greenberg told WBAL. Her dad called her "his angel."


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