- Fastq Manipulation and Quality Control
- Format help for Tabular/BED/Interval Datasets
- Understanding compressed fastq data (fastq.gz)
- Common datatypes explained
- Input datatype misassignment and errors
Most tools that accept FASTQ data expect it to be in a specific FASTQ version: .fastqsanger
.fastqsanger datatype must be assigned to each FASTQ dataset.
- Watch the FASTQ Prep Illumina video for a complete walk-through
- Run FastQC first to assess the type
- Run FASTQ Groomer if the data needs to have the quality scores rescaled
- If you are certain that the quality scores are already scaled to Sanger Phred+33 (the result of an Illumina 1.8+ pipeline), the datatype ".fastqsanger" can be directly assinged. Click the icon to reach the Edit Attributes form. In the center panel, click on the "Datatype" tab (3rd), enter the datatype ".fastqsanger", and save. Metadata will assign, then the dataset can be used.
- Run FastQC again on the entire dataset if any changes were made to the quality scores for QA
- If you are not sure what type of FASTQ data you have (maybe it is not Illumina?), see the help directly on the FASTQ Groomer tool for information about types.
- For Illumina, first run FastQC on a sample of your data (how to read the full report). The output report will note the quality score type interpreted by the tool. If not ".fastqsanger", run FASTQ Groomer on the entire dataset. If '.fastqsanger", just assign the datatype.
- For SOLiD, run NGS: Fastq manipulation → AB-SOLID DATA → Convert, to create a ".fastqcssanger" dataset. If you have uploaded a color space fastq sequence with quality scores already scaled to Sanger Phred+33 (".fastqcssanger"), first confirm by running FastQC on a sample of the data. Then if you want to double-encode the color space into psuedo-nucleotide space (required by certain tools), see the instructions on the tool form Fastq Manipulation for the conversion.
- If your data is FASTA, but you want to use tools that require FASTQ input, then using the tool NGS: QC and manipulation → Combine FASTA and QUAL. This tool will create "placeholder" quality scores that fit your data. On the output, click the icon to reach the Edit Attributes form. In the center panel, click on the "Datatype" tab (3rd), enter the datatype ".fastqsanger", and save. Metadata will assign, then the dataset can be used.