.BCL File Extension

A .BCL file is a Illumina Base Call File, created by Illumina.

Open with Illumina CASAVA. Available for Windows.

What is a .BCL file?

The file extension .BCL stands for an Illumina Base Call File. This type of file is created by machines that read DNA sequences, specifically those made by a company called Illumina. Some of the machines that produce .BCL files include the HiSeq and MiSeq. When these machines read the DNA, they go through it cycle by cycle, and for each cycle, they record two things: the base call, which is the identification of the DNA base (A, T, C, or G), and the quality score, which tells us how confident the machine is about each base it has identified.

The information saved in a .BCL file is very important for scientists and researchers who are studying genetics because it helps them understand the sequence of DNA they are working with. However, to analyze this data, they need to use specific software. One of the programs that can open and work with .BCL files is called Illumina CASAVA. This software can take the data from the .BCL file and analyze it to help researchers understand the DNA sequences.

Another program that can work with .BCL files is the Illumina BCL2FASTQ Conversion Software. This tool is used to convert the .BCL files into a different format known as QSEC. The QSEC format is also used for studying DNA, but it is compatible with a wider range of software tools, making the data more accessible for different types of analysis.

In summary, .BCL files are crucial for DNA sequencing and analysis, created by Illumina sequencing instruments. To use the data in these files, researchers can rely on specific software like Illumina CASAVA for direct analysis or use the Illumina BCL2FASTQ Conversion Software to convert the files into a more widely usable format.


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