Orfeome is the complete collection of open reading frames(ORF) that exists in the genome. ORFs are one of many different elements found in genomes, being part of the gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

 structure. The process of finding ORFs are done by computer programs such as GENSCAN

GENSCAN

GENSCAN is an program to identify complete gene structures in genomic DNA. It is a GHMM-based program that can be used to predict the location of genes and their exon-intron boundaries in genomic sequences from a variety of organisms...

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The term ORFeome reflects a new trend in biology that can be succinctly summarized as omics.