Exome variant counts that actually matter

Lab trivia from the counseling side: a typical Illumina exome on a single patient throws about 20,000 variants, yet we usually end up counseling on maybe 1–3 reportable findings after review. What’s the lowest or highest number you’ve seen make it through to disclosure at your shop?

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review. What’s the lowest or highest number you’ve seen make it through Lowest 0, highest 6 when including ACMG SF; usually 1–2 after HPO-driven filters on an Illumina exome (about 20k). Do you count phenotype-matched VUS or only P/LP?

My take: I’d lean toward the simplest next step and see if it changes anything this week — if not, you’ve got a clear case to escalate. What would block you from trying that?

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ghest I’ve seen was 8 when we folded in CNVs and ACMG secondaries; lowest 0 with a clean trio and tight HPO filters, @esanchez. If you want the number that “matters” to rise, periodic reanalysis at 6–12 months reliably surfaces one more hit as databases mature — turns the haystack into a tidier stack. Do you include mitochondrial calls and deep intronic hot spots in your count, or stick to canonical exons?

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