Hello, Luke.
Thank you for your question about downloading sequence in FASTA format from the UCSC Genome Browser.
If you unzip the gzip file, it will be a plain text file. It is just a compression algorithm that makes the file smaller which can be useful for downloading large amounts of sequence. Since you're downloading the sequence of a single gene, you could likely just select "plain text" as the output option.
If you want specific regions, not just a gene, you will need to use the custom track method as described in the FAQ you mentioned. If you are using that method, you'll need to be sure to select Group > Custom Tracks and Track > "Your Track Name" instead of the GENCODE track from your second screenshot.
If you have any further questions, please reply to
gen...@soe.ucsc.edu. 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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