JavaScript must be enabled in order to use this site.Please enable JavaScript in your browser and refresh the page. Target regions BED file formats Target regions files use a BED file format in 3‑column, 4‑column, 6‑column, and 8‑column formats. Related Topics Parent topic: BED file formats and examples Child Topics3-column target regions BED file format 4-column target regions BED file format 6-column target regions BED file format 8-column target regions BED file format BED files generated by Ion AmpliSeq™ Designer custom designs