Ellensburg, Wash., is home to a truly unique young man: 12-year-old Brenden Adams, who is more than seven feet tall and, incredibly, still growing.
He towers over his classmates and even his teacher, Gretchen Holmstrom, who jokingly quipped, "I'm 5'9," so I never look up to sixth graders -- until this year…never say never!"
And though friends say Brenden is just a regular kid, he's obviously not like anybody else. He has to duck through most doorways and sit sideways at his school desk because his knees don't fit under it.
In his mom's sport utility vehicle, he has to fold down the second row of seats, sit in the third row and stretch his legs out over the middle row in order to sit comfortably. His shoe size? 18 and still growing.
Brenden is one-of-a-kind, and it's not just his height. Everything about him is different. His mom, Debbie Ezell, said he requires a team of doctors and multiple medical visits simply to stay on top of his ever-changing and expanding frame. He has enormous joints, fatty tumors, even extra teeth, 12 of which were recently removed.
Amazingly, his dad, Willie Adams, said there was no hint of any of this when Brenden was born at 7 pounds, 3 ounces and 19 1/2 inches in length. His mom says they first started to notice something was different at his 2 month check-up. "They said, these measurements just aren't right. He's too long," Ezell said. "And at four months, he had all of his teeth."
Then mom and dad got the news that any parent would dread. Doctors and medical experts told them they had no idea what was causing the problem with their child. "I still haven't seen anyone like Brenden," says Dr. Melissa Parisi, his geneticist at Children's Hospital in Seattle. Parisi has been treating Brenden since he was four years old, when, she said, "he was the size of a typical 8-year-old boy."
"I was terrified," his father said, "and no one could ever give us an answer what the outcome would be or what the expectancy would be."
Brenden's mom agreed, "That's the worst part…not knowing."
For years, doctors continued to search for the source and an answer to Brenden's unstoppable growth. He went through multiple tests and X-rays as medical experts tried to determine what was going on inside Brenden's body.
Then, finally, a breakthrough -- when Brenden was eight years old and already the size of an adult.
"I have to say that the hematologists and oncologists here actually helped us figure it out," admits Parisi. "He has a very unusual rearrangement of his genetic material. It's what's called an inversion of chromosome-12 and it affects every single cell in his body."
Chromosomes, you may remember, come in pairs. But in Brenden's case, his 12th chromosomes don't match. Somehow -- experts still don't know why -- the middle of one of them broke off, flipped around and re-attached, disrupting a critical gene that controls growth. And that's what experts believe is causing Brenden's excessive growth and other symptoms and what makes his case the only one of its kind.
"This gene is functioning despite the regulation that it shouldn't be," said Dr. Gad Kletter, Brenden's endocrinologist at Swedish Hospital in Seattle. "It's over-functioning. He was predicted to be over eight foot tall."
Now that doctors finally figured out what was causing Brenden's skyrocketing height, they still had another mystery to solve: how to stop it? And since Brenden is believed to be the only person in the world with the condition, there was no clear-cut answer.
Then, Kletter had an idea that seemed a little crazy -- shots of testosterone to jump start puberty and speed up Brenden's growth. It's puberty, he explained, that signals the body to stop growing.
"We induced puberty," explained Kletter, "to fuse the bones and stop the growth."
And so far, the shots seem to be successful. Brenden's growth has slowed down.
To make life a little easier at home, Brenden's mom had a home built specifically to fit someone of Brenden's enormous proportions.
"It's a lot easier going through the doors and stuff than the last house we had," Brenden said. "The doors are a lot taller and so are the ceilings."
Coincidentally, on the day ABC News visited Brenden's school, his class was working on a soul-searching exercise. Perhaps not surprisingly, Brenden wrote that he wishes people would see "how he's just like everyone else."
Happily, some already do.
"He's really nice and caring," a friend, Tucker, said.
His stepsister, Sierra, added: "He's an extremely good person."
What does the future hold for him?
"It's unknown," said Kletter. "No other case is reported, nothing to look at -- it's an uncharted sea."