GeneID is a unique identifier that is assigned to a gene record in Entrez Gene. It is an integer and is species specific. In other words, the integer assigned to dystrophin in human is different from that in any other species. For genomes that had been represented in LocusLink, the GeneID is the same as the LocusID. The GeneID is reported in RefSeq records as a 'db_xref' (e.g. /db_xref="GeneID:856646", in GenBank format).