Figure 2. Genetic background affects regenerating axons in the optic nerve following optic nerve crush. The figure is a series of photomicrographs from 11 optic nerves selected from nine strains of mice. The first two images on the far left are from control mice that did not receive the regeneration treatment before optic nerve crush (Control C57BL/6J and Control DBA/2J). All of the remaining nerves were from animals in which Pten was knocked down and a mild inflammatory response was induced. The strain with the least regeneration was BXD102, and the strain with the greatest regeneration was BXD29. Red asterisks represent the crush site. Scale bar = 200 µm.