Whole Exome Sequencing (WES) is a targeted approach focusing on the protein-coding regions of the genome (around 1-2%). The exome encompasses a significant portion of known disease-causing mutations, it is an affordable choice for various genetic studies where focusing on protein-coding regions suffices for research or clinical objectives.
WES begins with DNA extraction, followed by library preparation involving fragmenting DNA and adding adapters. Next is exome capture, where target-specific probes enrich DNA fragments corresponding to exonic regions, the prepared exome library undergoes high-throughput sequencing.
Bioinformatic analysis includes aligning reads to a reference genome and identifying genetic variants within exonic regions, such as single nucleotide variants (SNVs), insertions, deletions, and structural variations. In the NF Genomics protocol, TWIST Comprehensive Exome Panel is utilized, covering over 99% of protein-coding genes, with a design size of 41.2 Mb and targeting a total of 36.8 Mb, including an expanded content of RefSeq and GENCODE databases.