Which sequencing approach tends to yield more incidental findings due to broad data?

• A. Whole genome sequencing.
• B. Whole exome sequencing.
• C. Targeted gene panels.
• D. Sanger sequencing.

Answer: (A)

Broader data leads to more incidental findings. Whole genome sequencing analyzes the entire genome, including coding regions, noncoding regions, and regulatory elements. Because you’re surveying the whole genome, you uncover variants across many genes and regions that aren’t related to the patient’s current clinical concern, which increases the chance of incidental, potentially actionable, or uncertain information showing up.

In comparison, whole exome sequencing focuses on the coding portions of genes (the exons). This still yields many clinically relevant variants, but it misses most noncoding regions, so the amount of incidental information is smaller than with genome sequencing. Targeted gene panels examine a predefined set of genes tied to a specific phenotype or condition, so their data scope is narrow and incidental findings are comparatively rare. Sanger sequencing is a targeted, gene-by-gene method used for validation or testing a limited region, producing even fewer incidental findings.

So the broadest data set—the full genome—naturally produces the most incidental findings due to the sheer breadth of information analyzed.