By Leslie Josephs

Jesse Curlee is on a mission to stamp out textile trickery, one strand of DNA at a time.

As president of Supima, the three-decade veteran of the textile industry is tasked with ensuring that the brand of premium U.S.-grown cotton touted on labels, such as those on Brooks Brothers and L.L. Bean shirts, is legit.

When a textile mill in Hong Kong flagged substandard yarn from a spinner in India, Mr. Curlee shipped a sample of the fiber off to Long Island for a genetic test. Supima canceled the Indian supplier’s license after the results showed the fabric misleadingly was of a cheaper cotton.