Genetic Information

Gene & Transcript Details

Gene
NF1
Transcript
NM_000267.3 MANE Select
Total Exons
Reference Sequence
NC_000017.10
Alternative Transcripts
IDStatusDetails
NM_000267.1 Alternative 8959 nt | 212–8668
NM_000267.3 Alternative 12381 nt | 384–8840
NM_000267.2 Alternative 12331 nt | 334–8790

Variant Details

HGVS Notation
NM_000267.3:c.2747A>G
Protein Change
N916S
Location
Exon 21 (Exon 21 of )
21
5'Exon Structure3'
Functional Consequence
Loss of Function
Alternate Identifiers

Clinical & Population Data

Population Frequency

gnomAD
Global Frequency
0.00239 in 100,000
Extremely Rare
ACMG Criteria Applied PM2
This variant is absent or extremely rare in population databases (PM2 criteria applies).

ClinVar

Open
Classification
Uncertain Significance (VUS)
2 publications
Publications List
Clinical Statement

"This variant has been reported in ClinVar as Uncertain significance (6 clinical laboratories) and as Likely benign (2 clinical laboratories)."

COSMIC Somatic Evidence

Open
COSMIC ID
COSM4384978
Recurrence
1 occurrences
PM1 Criteria
Not Applied
COSMIC Database Preview
COSMIC Preview
Accessing full COSMIC database details requires institutional login or subscription.

Functional Impact & Domains

Functional Domain

Hotspot Status
Not a hotspot
Domain Summary
This variant is not located in a mutational hotspot or critical domain.
Related Variants in This Domain
No evidence of other pathogenic variants at this position in gene NF1.

Functional Studies & Therapeutic Relevance

Functional Summary

The NF1 N916S variant has not been functionally characterized.

Database Previews
OncoKB
OncoKB Preview
JAX-CKB
JAX-CKB Preview

Click on previews to view full database entries. External databases may require institutional access.

Computational Analysis

Pathogenicity Predictions

SpliceAI
Predictor Consensus
Mixed/VUS
PP3 Applied
No
REVEL Score
0.0
Threshold: ≥0.75 = PP3 applied

SpliceAI Scores

Window: ±500bp
Effect Type Score Position
- Acceptor Loss (AL) 0.01 -108 bp
- Donor Loss (DL) 0.0 -41 bp
+ Acceptor Gain (AG) 0.0 -252 bp
+ Donor Gain (DG) 0.01 -130 bp
High impact (≥0.5) Medium impact (0.2-0.49) Low impact (<0.2)

VCEP Guidelines

Applied ACMG/AMP Criteria (VCEP Specific)

Filter Criteria:
PVS1

PVS1 (Not Applied)

According to standard ACMG guidelines, the rule for PVS1 is: "Null variant (nonsense, frameshift, canonical ±1 or 2 splice sites, initiation codon, single or multi-exon deletion) in a gene where loss of function (LOF) is a known mechanism of disease." The evidence for this variant shows that it is a missense change (p.N916S), not a null variant. Therefore, this criterion is not applied.

PS1

PS1 (Not Applied)

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 previously established pathogenic variant at the same amino acid (N916S). Therefore, this criterion is not applied.

PS2

PS2 (Not Applied)

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." There is no de novo information available for this variant. Therefore, this criterion is not applied.

PS3

PS3 (Not Applied)

According to standard ACMG guidelines, the rule for PS3 is: "Well-established in vitro or in vivo functional studies supportive of a damaging effect on the gene or gene product." There are no functional studies for NF1 p.N916S. Therefore, this criterion is not applied.

PS4

PS4 (Not Applied)

According to standard ACMG guidelines, the rule for PS4 is: "The prevalence of the variant in affected individuals is significantly increased compared to controls." There are no case–control or case series data for this variant. Therefore, this criterion is not applied.

PM1

PM1 (Not Applied)

According to standard ACMG guidelines, the rule for PM1 is: "Located in a mutational hot spot and/or critical and well-established functional domain without benign variation." There is no evidence that N916 lies within a recognized NF1 mutational 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) in Exome Sequencing Project, 1000 Genomes Project, or ExAC." The evidence for this variant shows an extremely low population frequency in gnomAD (MAF=0.00239%). Therefore, this criterion is applied at Moderate strength.

PM3

PM3 (Not Applied)

According to standard ACMG guidelines, the rule for PM3 is: "For recessive disorders, detected in trans with a pathogenic variant." NF1 is an autosomal dominant disorder, and no recessive trans data are applicable. Therefore, this criterion is not applied.

PM4

PM4 (Not Applied)

According to standard ACMG guidelines, the rule for PM4 is: "Protein length changes due to in-frame deletions/insertions in a non-repeat region or stop-loss variants." This is a missense change without protein length alteration. Therefore, this criterion is not applied.

PM5

PM5 (Not Applied)

According to standard ACMG guidelines, the rule for PM5 is: "Novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen before." There are no known pathogenic missense variants at residue N916. Therefore, this criterion is not applied.

PM6

PM6 (Not Applied)

According to standard ACMG guidelines, the rule for PM6 is: "Assumed de novo, but without confirmation of paternity and maternity." No de novo or parental data exist. Therefore, this criterion is not applied.

PP1

PP1 (Not Applied)

According to standard ACMG guidelines, the rule for PP1 is: "Cosegregation with disease in multiple affected family members." There are no segregation data available for this variant. Therefore, this criterion is not applied.

PP2

PP2 (Not Applied)

According to standard ACMG guidelines, the rule for PP2 is: "Missense variant in a gene that has a low rate of benign missense variation and where missense variants are a common mechanism of disease." NF1 disease mechanism is primarily loss-of-function, and missense is not the predominant mechanism. Therefore, this criterion is not applied.

PP3

PP3 (Not Applied)

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 computational evidence is mixed and SpliceAI predicts no significant splicing impact. Therefore, this criterion is not applied.

PP4

PP4 (Not Applied)

According to standard ACMG guidelines, the rule for PP4 is: "Patient’s phenotype or family history is highly specific for a disease with a single genetic cause." No specific phenotype or clinical data are provided. Therefore, this criterion is not applied.

PP5

PP5 (Not Applied)

According to standard ACMG guidelines, the rule for PP5 is: "Reputable source reports variant as pathogenic or likely pathogenic without evidence." No reputable source has reported this variant as (likely) pathogenic. Therefore, this criterion is not applied.

BA1

BA1 (Not Applied)

According to standard ACMG guidelines, the rule for BA1 is: "Allele frequency is >5% in population databases." The allele frequency of 0.00239% is far below 5%. Therefore, this criterion is not applied.

BS1

BS1 (Not Applied)

According to standard ACMG guidelines, the rule for BS1 is: "Allele frequency is greater than expected for disorder." The frequency (0.00239%) does not exceed the expected threshold for NF1. Therefore, this criterion is not applied.

BS2

BS2 (Not Applied)

According to standard ACMG guidelines, the rule for BS2 is: "Observed in a healthy adult individual for a dominant disorder with full penetrance." No well‐phenotyped healthy individuals carrying this variant are reported. Therefore, this criterion is not applied.

BS3

BS3 (Not Applied)

According to standard ACMG guidelines, the rule for BS3 is: "Well-established functional studies show no damaging effect." No functional studies exist. Therefore, this criterion is not applied.

BS4

BS4 (Not Applied)

According to standard ACMG guidelines, the rule for BS4 is: "Lack of segregation in affected family members." No segregation studies are available. Therefore, this criterion is not applied.

BP1

BP1 (Supporting)

According to standard ACMG guidelines, the rule for BP1 is: "Missense variant in a gene for which primarily truncating variants are known to cause disease." NF1 pathogenic variants are predominantly truncating and this is a missense change. Therefore, this criterion is applied at Supporting strength.

BP2

BP2 (Not Applied)

According to standard ACMG guidelines, the rule for BP2 is: "Observed in trans with a pathogenic variant for a dominant disorder or in cis with a pathogenic variant." No such observations are reported. Therefore, this criterion is not applied.

BP3

BP3 (Not Applied)

According to standard ACMG guidelines, the rule for BP3 is: "In-frame deletions/insertions in a repetitive region without a known function." This is not an indel. 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." While in silico predictions are mixed, SpliceAI predicts no splicing impact (score 0.01) and several tools predict benign. Therefore, this criterion is applied at Supporting strength.

BP5

BP5 (Not Applied)

According to standard ACMG guidelines, the rule for BP5 is: "Variant found in a case with an alternate molecular basis for disease." No such case is described. Therefore, this criterion is not applied.

BP6

BP6 (Supporting)

According to standard ACMG guidelines, the rule for BP6 is: "Reputable source reports variant as benign or likely benign without evidence." Two clinical laboratories in ClinVar have classified this variant as likely benign without detailed evidence. Therefore, this criterion is applied at Supporting strength.

BP7

BP7 (Not Applied)

According to standard ACMG guidelines, the rule for BP7 is: "Synonymous variant with no impact on splicing and no conserved nucleotide." This variant is missense, not synonymous. Therefore, this criterion is not applied.