Differences Between Ensembl, Gencode, RefSeq and UCSC

Cited from "Question: Difference Between Ensembl Databases In Ucsc Table Browser"

"Vega is a browser of the manually curated Havana gene set. Ensembl also perform automatic annotation of genes using protein and nucleotide sequence databases, such as EMBL, Uniprot and RefSeq. Ensembl use the GENCODE gene set, which is made up of the Havana and Ensembl automatic gene set. Genes within the GENCODE set are labelled as being either Ensembl (from the automatic annotation), Havana (from the manual annotation) or merged (exact match between the automatic and manual annotation)."
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