Brooke Greenberg (born January 8, 1993), is a 17 year old girl from Reisterstown, Maryland, who has remained physically and cognitively similar to a toddler, despite her increasing age. She is about 30 inches (76 cm) tall, weighs about 16 pounds (7.3 kg), and has an estimated mental age of 9 months to 1 year. Brooke’s doctors have termed her condition Syndrome X.

Brooke was born on January 8, 1993 at Sinai Hospital in Baltimore, Maryland, one month prior to her due date, weighing just four pounds (1.8 kg). She was born with anterior hip dislocation, a condition which caused her legs to be swiveled upwards, awkwardly, toward her shoulders; this was corrected surgically. Otherwise, Brooke appeared to be a normal infant.

In her first six years, Brooke Greenberg went through a series of unexplained medical emergencies from which she recovered. She had seven perforated stomach ulcers. She also suffered a seizure. This was followed by what was later diagnosed as a stroke; weeks later, no damage was detected. At age five, Brooke had a mass in her brain that caused her to sleep for 14 days. The doctors diagnosed the mass as a brain tumor. However, Brooke later awoke, and physicians found no tumor present. Brooke’s pediatrician, Dr. Lawrence Pakula, states that the source of her sudden illness remains a mystery.

Over the past several years, the Greenbergs visited many specialists, looking for an explanation for their daughter’s strange condition, and found she has a mutation in Chromosome 1. In 2001, when Dateline documented Brooke, she was still the size of a six-month-old infant, weighing just 13 lb (5.9 kg) at 27 inches (69 cm) tall. The family still had no explanation. Brooke Greenberg’s mother Melanie said: “They [the specialists] just said she’ll catch up. Then we went to the nutritionist, the endocrinologist. We tried the growth hormone…”. The growth hormone treatment had no effect. Howard, Brooke’s father, said: “I mean she did not put on an ounce or she did not grow an inch … That’s when I knew there was a problem.” After the growth hormone administration failed, the doctors, unable to diagnose a known condition, named her condition Syndrome X.

The Greenbergs made many visits to nearby Johns Hopkins Children’s Center, and even took Brooke to New York’s Mount Sinai Hospital, searching for information about their daughter’s condition. When geneticists sequenced Greenberg’s DNA, they found that the genes associated with the premature aging diseases were normal, unlike the mutated versions in patients with Werner syndrome and progeria.

In 2006, Dr. Richard Walker of the University of South Florida College of Medicine, said that Brooke’s body is not developing as a coordinated unit, but as independent parts that are out of sync. She has never been diagnosed with any known genetic disorder or chromosomal abnormality that would help explain why.

In 2009, Walker said: “There’ve been very minimal changes in Brooke’s brain … Various parts of her body, rather than all being at the same stage, seem to be disconnected.” Walker noted that Greenberg’s brain, for example, is not much more mature than that of a newborn infant. He estimates her mental age at around 9 months to a year old. Brooke can make gestures and recognize sounds, but cannot speak. Her bones are like those of a ten-year-old, and she still has her baby teeth, which have an estimated developmental age of about 8 years. Said Walker, “We think that Brooke’s condition presents us with a unique opportunity to understand the process of aging.”

Her telomeres seem to be shortening at the normal rate.

7 year old

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