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Nonsense or Frameshift

Predicted to undergo NMD b

Not predicted to undergo NMD b

Exon is present in biologically-relevant transcript(s) and truncation between codons 1-581

Exon is absent from biologically-relevant transcript(s)

PVS1

N/A

Truncated/altered region is critical to protein function (codons 582-620)

Role of region in protein function is unknown (codons 621-676)

LoF variants in this exon are frequent in the general population and/or exon is absent from biologically-relevant transcript(s)

PVS1_Moderate

N/A

PVS1_Supp

PVS1_Supp

LoF variants in this exon are not frequent in the general population and exon is present in biologically-relevant transcript(s)

Variant removes >10% of protein

Variant removes <10% of protein

GT--AG

1,2 splice

sites a

Exon skipping or use of a cryptic splice site disrupts reading frame and is predicted to undergo NMD b

Exon skipping or use of a cryptic splice site preserves reading frame

Truncated/altered region is critical to protein function (codons 582-620) c

Role of region in protein function is unknown (codons 621-676)

LoF variants in this exon are frequent in the general population and/or exon is absent from biologically-relevant transcript(s)

LoF variants in this exon are not frequent in the general population and exon is present in biologically-relevant transcript(s)

Variant removes >10% of protein

Truncated/altered region is critical to protein function c

PVS1_Moderate

N/A

PVS1_Supp

PVS1_Supp

PVS1_Strong

Variant removes <10% of protein

Exon skipping or use of a cryptic splice site disrupts reading frame and is NOT predicted to undergo NMD b

Deletion

(Single exon to full gene)

Single to multi exon deletion –

Disrupts reading frame and is predicted to undergo NMD b

Single to multi exon deletion –

Preserves reading frame

Full gene deletion

Exon is present in biologically-relevant transcript(s)

Truncated/altered region is critical to protein function c

Exon is absent from biologically-relevant transcript(s)

Role of region in protein function is unknown

LoF variants in this exon are frequent in the general population and/or exon is absent from biologically-relevant transcript(s)

PVS1 d

Truncated/altered region is critical to protein function c

PVS1

N/A

PVS1_Strong

N/A

PVS1_Strong

PVS1_Moderate

PVS1_Strong

Duplication

(≥1 exon in size and must be completely contained within gene)

Proven in tandem

Presumed in tandem

Proven not in tandem

Reading frame disrupted and NMD predicted to occur

No or unknown impact on reading frame and NMD

Reading frame presumed disrupted and NMD predicted to occur

PVS1

N/A

PVS1_Strong

N/A

Initiation Codon

Different functional transcript uses alternative start codon

No known alternative start codon in other transcripts

≥1 pathogenic variant(s) upstream of closest potential in-frame start codon

No pathogenic variant(s) upstream of closest potential in-frame start codon

PVS1_Supp

PVS1_Moderate

N/A

Single to multi exon deletion –

Disrupts reading frame and is NOT predicted to undergo NMD b

LoF variants in this exon are not frequent in the general population and exon is present in biologically-relevant transcript(s)

Variant removes >10% of protein

Variant removes <10% of protein

Role of region in protein function is unknown

LoF variants in this exon are frequent in the general population and/or exon is absent from biologically-relevant transcript(s)

LoF variants in this exon are not frequent in the general population and exon is present in biologically-relevant transcript(s)

Variant removes >10% of protein

N/A

PVS1_Strong

PVS1_Moderate

Variant removes <10% of protein

Evidence that truncation between codons 530-581 is not subject to NMD

PVS1_Strong

Exon is present in biologically-relevant transcript(s) and truncation between codons 1-581

Exon is absent from biologically-relevant transcript(s)

PVS1

N/A

Evidence that truncation between codons 530-581 is not subject to NMD

PVS1_Strong

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