The “Summer I Turned Pretty” star Gavin Casalegno’s Dunkin’ ad is coming under scrutiny and sparking yet another debate over promoting certain “genetics.” In the new ad for the chain, Casalegno sits with his legs in a pool before standing up and telling the camera his tan is natural. “Look, I didn’t ask to be the king of summer. It just happened,” he says. “This tan? Genetics. I just got my color analysis back. Guess what? Golden summer, literally.” 6 Gavin Casalegno’s new Dunkin’ ad is coming under scrutiny over its use of the word “genetics.” 6 In the ad,...