The National Institutes of Health altered a key portion of its website last week around the time it disclosed to Congress that experiments it funded in China met the definition of gain-of-function. The federal agency, known as the NIH, had a detailed explanation of gain-of-function research on its site, noting that the term refers to any research that modifies a biological agent in a way that confers new or enhanced activity to that agent. But the explanation was wiped between Oct. 19 and Oct. 21—possibly ahead of the NIH’s most recent disclosures on Oct. 20 about research it funded in...