Antibiotic-free chloroplast genetic engineering - an environmentally friendly approach

Chloroplast genetic engineering offers several advantages over nuclear gene tic engineering, including gene containment and hyperexpression, However, i ntroducing thousands of copies of transgenes into the chloroplast genome am plifies the antibiotic resistance genes. Two recent articles report differe nt and novel strategies to either remove antibiotic resistance genes or sel ect chloroplast transformants without using these genes. This should elimin ate their potential transfer to microorganisms or plants and ease public co ncerns about genetically modified crops.