When performing NGS, when is enrichment/target capture of genomic sequences necessary?

You should consider target enrichment (target capture) if you are analyzing a subsection of the genome or performing deep sequencing to detect rare mutations. This allows you to reserve sequencing capacity for the region(s) of interest, and reduce the sequencing cost and time associated with data analysis. IDT xGen Lockdown Probes are excellent custom panels, but they can also be used for supplementing other capture panels to expand the target region or improve enrichment performance.