ASXL1 c.2011G>T, p.Ala671Ser

NM_015338.5:c.2011G>T
COSM110703

Classification Summary

Variant of Uncertain Significance (VUS)

This variant is absent from controls (PM2) and computational evidence supports benign (BP4), with a missense in a loss-of-function gene (BP1). No pathogenic evidence is present. Overall evidence remains insufficient to classify beyond VUS.

Population Frequency
0.0 in 100,000
Rare
ClinVar Classification
Uncertain Significance (VUS)
0 publications
REVEL Score
0.108
Likely Benign
COSMIC Recurrence
1 occurrences
No Criteria Applied
Classification Evidence
Very Strong (PVS)
None applied
Strong (PS/BS)
None applied
Moderate (PM/BA)
PM2
Supporting (PP/BP)
BP1 BP4
Created: 2025-05-23T09:31:21.105299

Genetic Information

Gene & Transcript Details
Gene
ASXL1
Transcript
NM_015338.6 MANE Select
Total Exons
13
Strand
Forward (+)
Reference Sequence
NC_000020.10
Alternative Transcripts
ID Status Details
NM_015338.5 RefSeq Select 13 exons | Forward
NM_015338.4 Alternative 13 exons | Forward
NM_015338.3 Alternative 13 exons | Forward
Variant Details
HGVS Notation
NM_015338.5:c.2011G>T
Protein Change
A671S
Location
Exon 13 (Exon 13 of 13)
13
5' Exon Structure (13 total) 3'
Functional Consequence
Loss of Function
Related Variants
No evidence of other pathogenic variants at position 671 in gene ASXL1
Alternate Identifiers
COSM110703
Variant interpretation based on transcript NM_015338.6

Clinical Evidence

Population Frequency
Global Frequency
0.0 in 100,000
Extremely Rare
Global: 0.0%
0%
0.0005%
0.001%
0.01%
0.05%
1%+
ACMG Criteria Applied
PM2
This variant is not present in gnomAD (PM2 criteria applies).
ClinVar 2025-05-23T09:29:52.262947
Classification
Uncertain Significance (VUS)
Based on 2 submitter reviews in ClinVar
Submitter Breakdown
1 VUS
1 LB
Pathogenic
Likely Pathogenic
VUS
Likely Benign
Benign
Publications
0 publications
Clinical Statement
This variant has been reported in ClinVar as Likely benign (1 clinical laboratories) and as Uncertain significance (1 clinical laboratories).
COSMIC
COSMIC ID
COSM110703
Recurrence
1 occurrences
PM1 Criteria
Not Applied
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Functional Domain
Hotspot Status
Not a hotspot
Domain Summary

This variant is not located in a mutational hotspot or critical domain (0 mutations).

Related Variants in This Domain
No evidence of other pathogenic variants at position 671 in gene ASXL1

Functional Studies

Functional Impact
Summary
The ASXL1 A671S variant has not been functionally characterized, and its biological significance remains unknown.

Computational Evidence

Pathogenicity Predictions
REVEL Score
0.108
0.108
Likely Benign 0.0
Uncertain (Low) 0.2
Uncertain (Med) 0.5
Likely Pathogenic 0.75
REVEL scores ≥ 0.75 are considered strong evidence of pathogenicity (PP3)
Predictor Consensus
Mixed/VUS
PP3 Applied
No
Additional Predictors
Benign:
CADD: 1.66 polyphen_prediction: benign metasvm: T metalr: T primateai: T
Neutral: Show all
SpliceAI Scores Window: ±500bp
Effect Type Score Position
- Acceptor Loss
0.0
-291 bp
- Donor Loss
0.01
-142 bp
+ Acceptor Gain
0.0
-141 bp
+ Donor Gain
0.02
-6 bp
High impact (≥0.5)
Medium impact (0.2-0.49)
Low impact (<0.2)

VCEP Guidelines

Applied ACMG/AMP Criteria
PVS1
PVS1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PVS1 is: "Null variant (nonsense, frameshift, canonical ±1 or 2 splice sites, initiation codon, single exon deletion) in a gene where loss of function is a known mechanism of disease." The evidence for this variant shows: it is a missense change (c.2011G>T; p.Ala671Ser), not a null variant. Therefore, this criterion is not applied.
PS1
PS1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PS1 is: "Same amino acid change as a previously established pathogenic variant regardless of nucleotide change." The evidence for this variant shows: no known pathogenic variant results in p.Ala671Ser. Therefore, this criterion is not applied.
PS2
PS2 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PS2 is: "De novo (both maternity and paternity confirmed) in a patient with the disease and no family history." The evidence for this variant shows: no information on de novo status. Therefore, this criterion is not applied.
PS3
PS3 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PS3 is: "Well-established functional studies supportive of a damaging effect on the gene or gene product." The evidence for this variant shows: no functional studies have been performed. Therefore, this criterion is not applied.
PS4
PS4 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PS4 is: "Prevalence in affected individuals significantly increased compared with controls." The evidence for this variant shows: no case-control or prevalence data. Therefore, this criterion is not applied.
PM1
PM1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PM1 is: "Located in a mutational hot spot or well-established functional domain without benign variation." The evidence for this variant shows: location and domain data are insufficient to define a hot spot or critical domain. Therefore, this criterion is not applied.
PM2
PM2 (Moderate)
According to standard ACMG guidelines, the rule for PM2 is: "Absent from controls (or at extremely low frequency if recessive)." The evidence for this variant shows: it is not present in gnomAD or other population databases. Therefore, this criterion is applied at Moderate strength.
PM3
PM3 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PM3 is: "Detected in trans with a pathogenic variant for recessive disorders." The evidence for this variant shows: no data on trans configuration. Therefore, this criterion is not applied.
PM4
PM4 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PM4 is: "Protein length changes due to in-frame deletions/insertions or stop-loss variants." The evidence for this variant shows: it is a missense change without indel or stop-loss. Therefore, this criterion is not applied.
PM5
PM5 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PM5 is: "Novel missense change at an amino acid residue where a different pathogenic missense change has been seen." The evidence for this variant shows: no pathogenic missense has been reported at p.Ala671. Therefore, this criterion is not applied.
PM6
PM6 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PM6 is: "Assumed de novo, but without confirmation of paternity and maternity." The evidence for this variant shows: no de novo information is available. Therefore, this criterion is not applied.
PP1
PP1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PP1 is: "Co-segregation with disease in multiple affected family members." The evidence for this variant shows: no segregation data. Therefore, this criterion is not applied.
PP2
PP2 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PP2 is: "Missense variant in a gene with a low rate of benign missense variation and where missense variants are a common mechanism of disease." The evidence for this variant shows: ASXL1 disease mechanism is loss-of-function and missense variants are not established as a common mechanism. Therefore, this criterion is not applied.
PP3
PP3 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PP3 is: "Multiple lines of computational evidence support a deleterious effect on the gene or gene product." The evidence for this variant shows: REVEL score is 0.11 (<0.15) and SpliceAI is 0.02, supporting benign. Therefore, this criterion is not applied.
PP4
PP4 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PP4 is: "Patient's phenotype or family history highly specific for a disease with a single genetic etiology." The evidence for this variant shows: no phenotype or family history data. Therefore, this criterion is not applied.
PP5
PP5 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for PP5 is: "Reputable source reports variant as pathogenic, but without accessible evidence." The evidence for this variant shows: no reputable source reports it as pathogenic. Therefore, this criterion is not applied.
BA1
BA1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BA1 is: "Allele frequency is too high for the disorder." The evidence for this variant shows: absent from population databases. Therefore, this criterion is not applied.
BS1
BS1 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BS1 is: "Allele frequency is greater than expected for disorder." The evidence for this variant shows: absent from population databases. Therefore, this criterion is not applied.
BS2
BS2 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BS2 is: "Observed in healthy adult individuals for a dominant disorder with full penetrance." The evidence for this variant shows: no observations in healthy individuals. Therefore, this criterion is not applied.
BS3
BS3 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BS3 is: "Well-established functional studies show no damaging effect on protein function or splicing." The evidence for this variant shows: no functional studies available. Therefore, this criterion is not applied.
BS4
BS4 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BS4 is: "Lack of segregation in affected family members." The evidence for this variant shows: no segregation data. Therefore, this criterion is not applied.
BP1
BP1 (Supporting)
According to standard ACMG guidelines, the rule for BP1 is: "Missense variant in a gene where only loss-of-function causes disease." The evidence for this variant shows: ASXL1-associated disease is caused by truncating loss-of-function variants and this is a missense change. Therefore, this criterion is applied at Supporting strength.
BP2
BP2 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BP2 is: "Observed in trans with a pathogenic variant for dominant disorders or in cis with a pathogenic variant." The evidence for this variant shows: no data on cis/trans observation. Therefore, this criterion is not applied.
BP3
BP3 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BP3 is: "In-frame deletions/insertions in a repetitive region without known function." The evidence for this variant shows: it is a single nucleotide substitution. Therefore, this criterion is not applied.
BP4
BP4 (Supporting)
According to standard ACMG guidelines, the rule for BP4 is: "Multiple lines of computational evidence suggest no impact on gene or gene product." The evidence for this variant shows: REVEL score of 0.11, SpliceAI 0.02, and other in silico tools predict benign impact. Therefore, this criterion is applied at Supporting strength.
BP5
BP5 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BP5 is: "Variant found in a case with an alternate molecular basis for disease." The evidence for this variant shows: no data on alternate molecular findings. Therefore, this criterion is not applied.
BP6
BP6 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BP6 is: "Reputable source reports variant as benign, but without accessible evidence." The evidence for this variant shows: no such report. Therefore, this criterion is not applied.
BP7
BP7 (Not Applied) Strength Modified
According to standard ACMG guidelines, the rule for BP7 is: "Synonymous variant with no predicted impact on splicing." The evidence for this variant shows: it is a missense change. Therefore, this criterion is not applied.