Gene-centric pages in OMA give all the information specific to a single gene in OMA. The gene is found at the top, with its OMA ID and UniProt ID. Different sub-pages are available on the left-hand scrollable menu with specific information, including the orthologs, paralogs, gene information, isoforms, GO annotations, sequences, and local synteny.You ran a network analysis and found that the human gene with UniProt ID OR2L5_HUMAN is involved in an interesting pathway. Search for this gene on the OMA homepage.
OMA Groups are cliques of orthologs based on the orthology graph. In an OMA Group, all the genes are connected to each other by pairwise orthologous relations. For this reason, OMA Groups are typically conservative (they may exclude true orthologs) but have high confidence.Open the OMA Groups page of the gene from before. If you are starting the module from here search for the OMA Group 297702.
The evolution of a gene family describes the history of all the genes that shared a common ancestral gene. Those genes called homologs can be distinguished into orthologs if they start diverging by speciation and paralogs if they start diverging by duplication. In comparative genomics, gene families are a fundamental resource since they tend to represent the links between several organisms from a gene centric perspective and allow us to understand how genes and genomes have evolved over time.
A HOG is a set of genes that have descended from a common ancestral gene in a given ancestral species (i.e. at a specific taxonomic level). HOGs are hierarchical because groups defined at more recent clades are encompassed within larger groups that are defined at older clades, thus making them nested subfamilies.