Health: When Cells Stop Working

Nothing worries parents more than a sick infant--especially when nobody can figure out what's wrong. For Asher Gould's parents, the uncertainty lasted for the first three years of their son's life. Asher's older brother Sam, now 10, has always been pretty healthy. But a couple of months after he was born, Asher started having trouble feeding and was spotting his diapers with blood. The pediatrician decided he had an allergy to milk. Then, at 9 months, he couldn't crawl or sit up. The diagnosis this time was hypotonia, a vague term that basically means "poor muscle tone." With physical therapy, Asher walked at 17 months, but then a month later he caught a cold--and overnight lost half his vocabulary. Nobody could figure out what was going on.

Asher was almost 3 when he began preschool, and that's when the phone started ringing. He was falling down at school. He became weaker and weaker. And after a mild flu, he stopped eating. By Christmas he was emaciated, but with a big, distended belly. His intestines had all but stopped working, and nobody could figure out why. Maybe it was myopathy (a muscle disease) or some sort of nerve-wasting disorder. "Don't try to figure it out," advised a doctor. "Just put in a feeding tube."

But Asher's parents--Anne Reckling, a child psychologist, and David Gould, an administrator at a private school in Columbus, Ohio--were determined to get to the bottom of it. On the urging of someone on a myopathy e-mail discussion list, they went to see Dr. John Shoffner, a neurologist and geneticist at Horizon Molecular Medicine, a private group in Atlanta. A few weeks later, a fax arrived with Shoffner's diagnosis. Asher was suffering from a type of mitochondrial disease.

If the term is unfamiliar, that's no surprise. "When I began working on mitochondrial disease back in the '80s," says Shoffner, "people were still arguing over whether it even existed." Nobody is arguing about that anymore. In fact, doctors have now identified hundreds of different subtypes of the disorder. What they all have in common is a malfunction of the mitochondria--tiny substructures, or organelles, found inside every cell in the body. Their job is to convert food into a chemical called ATP that cells use for energy. When they go bad, all sorts of havoc is wreaked on the body. Depending on which types of cells are affected, mitochondrial disease can cause muscle wasting, nerve damage, seizures, stroke, blindness, deafness and more.

Officially, as many as 2 million Americans suffer from mitochondrial disease. But because defects in the mitochondria may underlie an astonishing range of very familiar illnesses, researchers are beginning to suspect that the real number is vastly higher. In the past few weeks alone, reports have come out in Cell, Nature and the Journal of Neuroscience implicating the mitochondria as factors in diseases such as Alzheimer's and Parkinson's. Indeed, says Dr. Vamsi Mootha, a Harvard Medical School researcher who won a MacArthur Foundation "genius" grant in 2004 for his work on mitochondria, "it looks like they're really important in diabetes, hypertension and many other common diseases--even in the aging process itself."