By VIVIAN NEREIM, Pittsburgh Post-Gazette

PITTSB URGH -- Two years ago, when Denise Snell's family physician told her that her son Malik should lose weight and referred her to a specialist, she brushed the idea off.

"We hesitated," said Snell, of Pittsburgh. "We thought we could make it on our own."

The story is straight out of Nancy Drew: A half-eaten corn dog found at the scene of a suburban office burglary yields DNA that links the crime to a man with 27 previous arrests.

But it's not fiction. It happened in Hennepin County, Minn., earlier this year.