I read a paper that is well written and a surprising development in the field of gene/DNA therapeutics, so I wanted to share and summarize it, with a special focus on molecular biology. The title says it all, but you gotta be careful not to jump to conclusions: it’s not the AAV that seems to be the problem, nor is it the miRNA targeting the disease-causing gene. It turns out that the way the construct is designed causes toxic responses in animals. Cover art is a collage of the new constructs tested by Megan S. Keiser et al.