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Introduction to FastQC

FastQC is a fundamental bioinformatics tool for quality control of high-throughput sequencing data. It rapidly analyzes raw sequence files to generate clear graphical reports on key metrics like base quality, GC content and adapter contamination. These reports allow researchers to quickly diagnose the health of their sequencing data before analysis.

By identifying potential issues such as low-quality reads or technical artifacts, FastQC ensures data integrity, guiding necessary pre-processing steps and improving the reliability of downstream applications like variant calling and RNA-seq. This makes it an essential first step in virtually any genomics workflow.

A Step-by-Step Guide to Execute the Tool

Before executing the tool, you must create a Job ID. You can customize this ID, or the job ID will be created by the tool on its own.

TIP: Without creating a JOB ID, you will not be able to access any options of the tool.

Create Job ID

Alternatively, you can fetch previous results by entering an existing job ID.

Fetch previous job by ID

This is the FastQC tool's application workspace page, where various options for analysing sequences are available. This tutorial will explain each option in detail.

FastQC Workspace

Uploading Files and Running the Analysis

Upload the fastq files in .fastq or .fastq.gz format by clicking on "Click to browse files".

Upload files section

The uploaded files and the number of files will be displayed below.

Uploaded files list

Click on "Run Analysis".

Run Analysis button

After clicking "Run Analysis", a pop-up will appear indicating that the analysis has started.

Analysis started pop-up

After the analysis has been completed, another pop-up will appear.

Analysis completed pop-up

Analyzing the QC Report

The plots after analysis will be shown below.

Quality control plots

The Summary table provides an overview of the status for each parameter, indicating whether it has passed, failed, or triggered a warning.

Summary table

FastQC has successfully completed its execution with a vital assessment of your raw sequencing data. Understanding each parameter in the report is important. This early identification of potential issues safeguards that you can make informed decisions on data trimming and filtering for accurate results for all subsequent bioinformatics analyses.