I am a physicist in biology (so take these with a grain of salt) and CRISPR is arguably the most exciting development there. This technique allows to edit DNA based on guiding RNAs which can be readily synthesized in contrast to DNA binding proteins required for targeted editing before. What's more the same technology can be used to adjust gene regulation too. These techniques are not only giving basic research a big boost, but also making many new treatments possible.

Another hot topic are organoid bodies and organs-on-a-chip. These are experimental systems where stem cells are turned to grow into structures similar to embryos or organs that allow the study of development and facilitate drug testing etc.

Thirdly, advances in sequencing made it possible to study what kind of bacteria live symbiotically within and on us. The composition of this so called microbiome seems to widely affect body and mind.

Finally, in my personal field, the simulation of how "simple" cells build complex structures and solve difficult tasks, the most exciting development is GPGPU :-)