Passing values for a geojson filter in Leaflet

I have a situation where I have a geojson layer in leaflet and I want to create a subset of this layer as a separate geojson to highlight specific features. What I am doing right now is passing in the subset manually as form a separate javascript file (the main feature is loaded as a topojson via omnivore). What I want to be able to, however, is pass the features to be included in the "highlight" geojson as an array of key values (or something similar) so that I can define the features to be included from within the script instead of having to manually pass it in externally.