GFF stands for 'general feature format' or 'gene finding format'; it is a tab-delimited file with 9 columns. There are several types of GFF files that use incompatible syntax. The original GFF format is GFF1. A variant called GTF is also used. GFF3 has been proposed to extend on GFF and to constrain the specification more tightly to avoid mutually-incompatible versions of GFF. The annotation file must be an .gff (Generic Feature Format Version 3 , GFF3) file.
Please see http://www.sequenceontology.org/resources/gff3.html for a detailed description of the Generic Feature Format (GFF).
To upload you data files, create a tabulated text file (.txt) containing the following information:
- Line 1: "# Sequence [tabulation] sequence number (optional)". You just have to write the word sequence for the program to start reading your data. The sequence number is optional.
- Line 2: "# Name [tabulation] chr number". This will identify the chromosome the probes contain information for.
- Line 3: "#Numer of hits [tabulation] number of hits". This tells the program how many lines of probes it has to read. In the case of the example, it will read 94972 lines in a row until the next set of probes (Sequence 2).
- Line 4: Leave blank space
- Line 5: Probe position, followed by tabulation and signal intensity of the probe, ie "probe [tabulation] signal".
NOTE: In between sequences, you have to leave a blank space.
You can download an example data set here.