The Medical Sleuth (Scientific American)

Posted on by Brendan Borrell


The patient had endured 20 years of pain: her calves had turned into two bricks,  and she now had trouble walking. A slew of doctors had failed to treat, let alone diagnose, her unusual condition. So when her x-rays finally landed on William A. Gahl’s desk at the National Institutes of Health, he knew immediately that he had to take her case.

Gahl is the scientist and physician who leads the Undiagnosed Diseases Program, which tries to unravel the underlying causes of, and find therapies for, mysterious maladies and known but rare conditions. Louise Benge’s x-rays had revealed that blood vessels in her legs and feet bore a thick coat of calcium that restricted blood flow. Benge’s sister, Paula Allen, along with several other members of the family, also shared the disorder. Over the course of several months Gahl identified the genetic root of the disorder—a mutation in a gene that regulates calcium—and he went on to propose a treatment with drugs already on the market. He continues to assess the treatment’s value.