What is a FASTQ file and how is it used in WGS (Whole Genome Sequencing) analysis?

The FASTQ file is the raw output file from the sequencing machine used in Ultra Whole Genome Sequencing (WGS), which decodes 100% of your DNA. This file contains all the unprocessed genetic data, specifically the DNA reads in the form of millions of strings of letters (A, C, G, T), along with quality scores indicating the reliability of each read.

The FASTQ is used by bioinformaticians and researchers who wish to perform detailed analyses of their DNA, such as alignment and variant identification from scratch. It is also useful for users who want to store their raw data for future analysis, for instance, in case new reference genomes are released.

FASTQ file characteristics:

Total completeness: It contains every read produced by the sequencer, without filtering any information.
Unbiased: It is not influenced by scientific limitations or specific reference genomes.

Limitations:

Not human-readable: You cannot directly “read” a FASTQ file to obtain information about your genetic traits. It needs to be processed to extract useful information.
Storage size: Given their large size, FASTQ files require significant hard drive space.

Formats and download:

In addition to FASTQ, we also offer the VCF format. You can download these files directly from your tellmeGen user account.

Technical requirements:

Operating system: Linux or macOS (command-line proficiency required).
RAM: Minimum 16 GB (32 GB or more recommended for analysis).
Storage: > 200 GB.

This format is suitable for advanced users who wish to perform a more detailed and specific analysis of their genetic data.