Barton Childs Dies

Barton Childs, the Johns Hopkins University professor who helped found the field of pediatric genetics, has died, reports the New York Times. He was 93. In the 1960s, Childs confirmed the Lyon hypothesis in humans. Based on mouse studies that hypothesis said that, in females' cells, one of their two X chromosomes is inactive and which one it is that is inactive occurs randomly. This, the Times adds, helped explain why women were less affected by certain genetic diseases. More recently, Childs said that researchers still have a lot of work to do to understand the meaning of genetic risk factors, and that was wary of some genetic testing companies. "We know that three people with exactly the same gene may have three different outcomes and that people with so-called disease genes may never get the disease," Childs said. Childs taught at Hopkins for nearly 70 years.