A MAN WHO LOOKS LIKE HE'S TURNING INTO A TREE, ON "PRIMETIME: MEDICAL MYSTERIES," AUGUST 12 ON ABC

On Tuesday, "Primetime: Medical Mysteries" reports on some of the strangest cases known to medicine, including a man in Indonesia who looks as if he's turning into a tree. The hour will also feature reports on a rare paralyzing condition that attacks first-time surfers and a disorder found among the most feminine of women -- who find out they are genetically male. The "Primetime" limited series, which examines cases that still leave scientists and doctors with unanswered questions when trying to explain the human body, airs TUESDAY, AUGUST 12 (10:00-11:00 p.m., ET) on ABC.

"Primetime" examines one man in Indonesia who looks as though he is turning into a tree. His hands and feet are 15 inches around and look like roots, while "bark" covers his body. Margaret Conley reports on the "perfect storm" of dermatology that is causing this bizarre case�the common HPV virus, to which most people have immunity -- and a genetic immune system problem that gives Dede, known in his country as "Tree Man," no immunity at all. Indonesian and American doctors puzzle over how to help him regain a normal life.

Then: David Muir reports on a mysterious and terrifying threat that could be lurking for beginner surfers -- not under the water, but in their own bodies. Muir speaks with two men who tried surfing for the first time on a beach vacation and became paralyzed from the waist down because of a rare complication known as Surfer's Myelopathy. Dr. James Pearce, who first documented this condition nearly 25 years ago, explains to "Primetime" that, when the spinal cord is hyper-extended, as when a surfer arches his back on the board, it can interrupt the blood flow to the spine causing what he calls a "stroke to the spine." For now, no medication or surgery is available to treat Surfer's Myelopathy. Many patients do recover, however, through intense physical therapy.

And: Imagine a woman who is feminine, attractive, and has always considered herself female, but as a teenager knew something was off. When she fails to get her period during adolescence, doctors discover that she has no uterus, no ovaries, but rather testicles, inside her body. Genetically, she's a boy, but despite her male chromosomes, she has more estrogen than most women. Juju Chang reports on Androgen Insensitivity Syndrome, where a woman has male chromosomes�an X and a Y instead of two Xs�yet she is more "female" in appearance than average women. An estimated 7,500 women in the U.S. have the condition, according to Dr. Charmian Quigley, a pediatric endocrinologist.

The hour will also feature a medical mystery designed for viewer participation. This segment, called "You Be the Doctor," allows viewers to assess medical clues and vote online or by text messaging their diagnosis as the show progresses. Why does a man's horrible headache last for weeks? And why does it hurt especially when he sneezes or turns his head?

Ann Reynolds and Terry Wrong are the senior producers of "Primetime: Medical Mysteries." Rudy Bednar is the executive producer.