Hello, José.
You are referring to the “Color track by codons” option in the track controls. This is a function of a genePred track. Track hubs support the bigGenePred format. Please see http://genome.ucsc.edu/goldenPath/help/bigGenePred.html for more information about the bigGenePred format and instructions for creating a bigGenePred track.
Please contact us again at gen...@soe.ucsc.edu if you have any further questions. Questions sent to that address will be archived in a publicly-accessible forum for the benefit of other users. If your question contains sensitive data, you may send it instead to genom...@soe.ucsc.edu.
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Steve Heitner
UCSC Genome Bioinformatics Group
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