How does CRISPR-Cas9 technology accurately target and modify specific sequences in the DNA of organisms, and what are the potential ethical implications of its use in human genetic engineering?

CRISPR-Cas9 technology uses a guide RNA to precisely target specific DNA sequences, allowing the Cas9 enzyme to create double-strand breaks at these locations. This enables precise genetic modifications. Ethical implications include concerns over unintended consequences, genetic inequality, and potential misuse in human genetic engineering.