Those are the words of the author, not me. They found that people who experience trauma bad enough to cause depression have elevated risk of death in the ensuing 11 years, but one particular allele disconnects the link. Some people are genetically more resilient to bad stuff in their life. We knew that, but it's nice to see confirmation of one way it happens.
This is an example of the general rule of life that people vary. Siblings growing up in an abusive household. One becomes an abusive parent, and one does not.