Helix Insight

Documentation / Classification / Criteria Reference

Criteria Reference

Complete reference for all 28 ACMG evidence criteria. 19 are evaluated automatically, 9 require manual curation, and 1 (PM5) is currently disabled.

Pathogenic Evidence (16 criteria)

PVS1Very Strongautomated

Null variant in gene where loss-of-function is a known disease mechanism

Conditions

Impact = HIGH

Consequence: frameshift, stop_gained, splice_acceptor, or splice_donor

Gene constraint: pLI > 0.9 OR LOEUF < 0.35

Exclusions

NMD-rescued transcripts

Stop-retained and stop-lost variants

HLA gene family

Databases: VEP (consequence, impact), gnomAD Constraint (pLI, LOEUF)

Does not evaluate reading frame rescue or alternative transcript usage

Last-exon truncation logic not implemented

VCEP gene-specific PVS1 applicability gate available for ~50-60 genes

PS1Strongautomated

Same amino acid change as an established pathogenic variant

Conditions

ClinVar: Pathogenic or Likely Pathogenic

ClinVar review stars >= 2

Databases: ClinVar

Matches exact variant, not amino acid position (PM5 matching is disabled)

PS2Strongmanual

De novo variant (confirmed paternity and maternity)

Requires trio sequencing data and confirmed parental relationships.

PS3Strongmanual

Functional studies show a deleterious effect

Requires curation of published functional assay data.

PS4Strongmanual

Prevalence significantly increased in affected individuals

Requires case-control study data or odds ratios.

PM1Moderateautomated

Located in a functional domain

Conditions

Variant overlaps a Pfam protein domain

Databases: VEP (domains)

All Pfam domains treated equally regardless of functional importance

PM2Moderateautomated

Absent from controls or at extremely low frequency

Conditions

gnomAD global AF < 0.0001 (0.01%)

Frequency data must be present (non-NULL)

Databases: gnomAD v4.1

ClinGen SVI PM2_Supporting downgrade not implemented

VCEP gene-specific PM2 thresholds available when enabled

PM3Moderateautomated

Detected in trans with a pathogenic variant for recessive disorders

Conditions

Compound heterozygote candidate flag = true

Inferred from genotype data without formal phasing

PM4Moderateautomated

Protein length change in a non-repetitive region

Conditions

In-frame insertion or deletion

Located within a Pfam functional domain

Not in a repetitive or low-complexity region

Exclusions

HLA gene family

Databases: VEP (consequence, domains)

PM5Moderatedisabled

Novel missense at known pathogenic amino acid position

Pending standardized protein-level coordinate matching in ClinVar preprocessing.

PM6Moderatemanual

Assumed de novo without confirmation

Requires family structure information not available in single-sample analysis.

PP1Supportingmanual

Cosegregation with disease in multiple affected family members

Requires multi-generational pedigree data.

PP2Supportingautomated

Missense in a gene with low rate of benign missense variation

Conditions

Missense variant

Gene constraint: pLI > 0.5

Databases: VEP (consequence), gnomAD Constraint (pLI)

PP3Supporting / Moderate / Strongautomated

Computational evidence supports a deleterious effect

Conditions

Path A (Missense): BayesDel_noAF with ClinGen SVI calibrated thresholds -- PP3_Strong (>= 0.518, +4 pts), PP3_Moderate (0.290-0.517, +2 pts), PP3_Supporting (0.130-0.289, +1 pt)

PM1 + PP3 double-counting guard: when PM1 applies alongside PP3_Strong, PP3 is downgraded to PP3_Moderate (combined cap at Strong equivalent)

Path B (Splice): SpliceAI max_score >= 0.2 AND PVS1 does not apply (ClinGen SVI double-counting guard). Always Supporting strength.

Databases: dbNSFP 4.9c (BayesDel_noAF), SpliceAI (max_score)

BayesDel_noAF excludes allele frequency to avoid circular reasoning with PM2/BA1/BS1

PP4Supportingautomated

Patient phenotype matches gene disease association

Conditions

>= 3 patient HPO terms match the gene HPO profile

OR >= 2 matches with highly specific gene (<= 5 total HPO associations)

Databases: HPO (gene-phenotype associations)

Requires patient HPO terms to be provided.

PP5Supportingautomated

Reputable source reports variant as pathogenic

Conditions

ClinVar: Pathogenic or Likely Pathogenic

Review stars >= 1 AND < 2 (lower confidence than PS1)

Databases: ClinVar

ClinGen SVI recommended retiring PP5; retained for maximum sensitivity.

Benign Evidence (12 criteria)

BA1Stand-aloneautomated

Allele frequency above 5%

Conditions

gnomAD global AF > 0.05 (5%)

Databases: gnomAD v4.1

BA1 overrides ALL other evidence including ClinVar. VCEP gene-specific BA1 thresholds may be lower.

BS1Strongautomated

Allele frequency greater than expected for disorder

Conditions

AD proxy (haploinsufficiency score = 3): AF >= 0.1%

AR proxy (default): AF >= 5%

Databases: gnomAD v4.1, ClinGen (haploinsufficiency_score)

VCEP gene-specific BS1 thresholds override generic logic when enabled

BS2Strongautomated

Observed in healthy adults for fully penetrant early-onset disorder

Conditions

gnomAD homozygote count > 15

Databases: gnomAD v4.1

BS3Strongmanual

Functional studies show no deleterious effect

Requires curation of published functional assay data.

BS4Strongmanual

Lack of segregation in affected family members

Requires family segregation data.

BP1Supportingautomated

Missense in a gene where primarily truncating variants cause disease

Conditions

Missense variant

MODERATE impact

pLI < 0.1 (LoF-tolerant gene)

Databases: VEP, gnomAD Constraint (pLI)

BP2Supportingautomated

Observed in trans with pathogenic for fully penetrant dominant

Conditions

Compound heterozygote candidate

ClinGen haploinsufficiency score = 30 (dosage sensitivity unlikely)

Databases: ClinGen

BP3Supportingautomated

In-frame indel in repetitive region without known function

Conditions

In-frame indel

Repetitive/low-complexity region OR not in any Pfam domain

Databases: VEP (consequence, domains)

BP4Supporting / Moderateautomated

Computational evidence suggests no impact

Conditions

BayesDel_noAF with ClinGen SVI calibrated thresholds -- BP4_Moderate (<= -0.361, -2 pts), BP4_Supporting (-0.360 to -0.181, -1 pt)

SpliceAI max_score must be < 0.1 (no predicted splice impact)

Databases: dbNSFP 4.9c (BayesDel_noAF), SpliceAI

BP5Supportingmanual

Variant found in case with alternate molecular basis

Requires case-level information about alternative diagnoses.

BP6Supportingautomated

Reputable source reports variant as benign

Conditions

ClinVar: Benign or Likely Benign

Review stars >= 1

Databases: ClinVar

ClinGen SVI recommended retiring BP6; retained for maximum sensitivity.

BP7Supportingautomated

Synonymous variant with no predicted splice impact

Conditions

Synonymous variant

Not in splice region

SpliceAI max_score <= 0.1

Databases: VEP, SpliceAI

Conservation filter intentionally omitted per Walker et al. 2023 Table S13.