It was with some amazement that I read about your comments, made tonight while campaigning in Texas, about a possible link between mercury in vaccines and autism.

According to Jake Tapper at ABC News, a Texas mother of a child with autism asked you about the Federal Court document, first reported on Huffington Post last Monday, in which Justice Department officials conceded that vaccines had aggravated one child's underlying medical condition, resulting in a diagnosis of autism.

Your...