Hello, Bogdan.
A very similar question was asked recently. Please see https://groups.google.com/a/soe.ucsc.edu/d/msg/genome/IEP_aZjQp_s/-XB_nPwWcEMJ. You can also view the schema of the RepeatMasker track by viewing the track description page (http://genome.ucsc.edu/cgi-bin/hgTrackUi?db=hg19&g=rmsk) and clicking the “View table schema” link.
I believe your question about the reference sequences of transposons that the program uses would be best directed to the folks at RepeatMasker.
Please contact us again at gen...@soe.ucsc.edu if you have any further questions. All messages sent to that address are archived on a publicly-accessible Google Groups forum. If your question includes 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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