I am trying to get a list of genes involved in "metabolism", similar to in this paper - https://www.nature.com/articles/s42003-019-0666-1.
In this paper, they state that they "accessed information of all human metabolic pathways from the Reactome pathways database version 68. Reactome pathways are arranged into several tiers with the Reactome term “metabolism” (Reactome ID: R-HSA-1430728), encompassing 68 different metabolic pathways (see https://reactome.org/PathwayBrowser/#/R-HSA-1430728). The first-tier pathways include sixteen curated metabolic pathways which involve 2325 genes."
How do I do something similar and download a list of all genes involved in metabolism?
Also any explanation of the "tiers" thing would be great! I.e. when the authors talk about "first-tier pathways", what does this actually mean?