17-31229286-G-C

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2PP2BP4

The NM_001042492.3(NF1):c.2671G>C(p.Val891Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,613,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.07

Variant links:

Genes affected

NF1 (HGNC:7765): (neurofibromin 1) This gene product appears to function as a negative regulator of the ras signal transduction pathway. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The mRNA for this gene is subject to RNA editing (CGA>UGA->Arg1306Term) resulting in premature translation termination. Alternatively spliced transcript variants encoding different isoforms have also been described for this gene. [provided by RefSeq, Jul 2008]

NF1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in the NF1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 399 curated pathogenic missense variants (we use a threshold of 10). The gene has 143 curated benign missense variants. Gene score misZ: 6.5427 (above the threshold of 3.09). Trascript score misZ: 8.4054 (above the threshold of 3.09). GenCC associations: The gene is linked to neurofibromatosis, familial spinal, hereditary pheochromocytoma-paraganglioma, neurofibromatosis type 1, Watson syndrome, neurofibromatosis-Noonan syndrome, Moyamoya disease, familial ovarian cancer.

BP4

Computational evidence support a benign effect (MetaRNN=0.39201736).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3 link	c.2671G>C	p.Val891Leu	missense_variant	Exon 21 of 58	ENST00000358273.9	NP_001035957.1	P21359-1
NF1	NM_000267.3 link	c.2671G>C	p.Val891Leu	missense_variant	Exon 21 of 57		NP_000258.1	P21359-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 link	c.2671G>C	p.Val891Leu	missense_variant	Exon 21 of 58	1	NM_001042492.3	ENSP00000351015.4		P21359-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152224

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000205

AC:

AN:

1461536

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727088

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000270

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000656

AC:

AN:

152342

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74500

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neurofibromatosis, type 1

Uncertain:2

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nov 18, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 891 of the NF1 protein (p.Val891Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with NF1-related conditions. ClinVar contains an entry for this variant (Variation ID: 404435). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt NF1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Juvenile myelomonocytic leukemia

Uncertain:1

Aug 05, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Uncertain:1

Apr 05, 2021

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2671G>C (p.V891L) alteration is located in exon 21 (coding exon 21) of the NF1 gene. This alteration results from a G to C substitution at nucleotide position 2671, causing the valine (V) at amino acid position 891 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Feb 17, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V891L variant (also known as c.2671G>C), located in coding exon 21 of the NF1 gene, results from a G to C substitution at nucleotide position 2671. The valine at codon 891 is replaced by leucine, an amino acid with highly similar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.001% (greater than 110000 alleles tested) in our clinical cohort.This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive.Since supporting evidence is limited at this time, the clinical significance of this alterationremains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.18

BayesDel_addAF

Pathogenic

0.23

BayesDel_noAF

Uncertain

0.090

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.60

D;.;T

Eigen

Benign

-0.0086

Eigen_PC

Benign

0.20

FATHMM_MKL

Uncertain

0.97

LIST_S2

Uncertain

0.90

D;D;D

M_CAP

Pathogenic

0.30

MetaRNN

Benign

0.39

T;T;T

MetaSVM

Uncertain

-0.12

MutationAssessor

Benign

0.90

L;L;.

PrimateAI

Uncertain

0.63

PROVEAN

Benign

-2.0

N;N;N

REVEL

Uncertain

0.42

Sift

Benign

0.078

T;T;T

Sift4G

Benign

0.15

T;T;T

Polyphen

0.0020

B;B;.

Vest4

0.19

MutPred

0.33

Loss of catalytic residue at V891 (P = 0.0101);Loss of catalytic residue at V891 (P = 0.0101);.;

MVP

0.97

MPC

0.68

ClinPred

0.55

GERP RS

5.5

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.31

gMVP

0.52

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over