17-31360564-T-G

Position:

chr17-31360564-T-G

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 1P and 6B. PP2BP4_ModerateBS2

The NM_001042492.3(NF1):c.8238T>G(p.Ile2746Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000458 in 1,461,854 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.000046 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:1

Conservation

PhyloP100: 0.512

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 Likely_benign. Variant got -5 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), NF1. . Gene score misZ 6.5427 (greater than the threshold 3.09). Trascript score misZ 8.4054 (greater than threshold 3.09). GenCC has associacion of gene with 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=0.17146406).

BS2

High AC in GnomAdExome4 at 67 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3 linkuse as main transcript	c.8238T>G	p.Ile2746Met	missense_variant	57/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3 linkuse as main transcript	c.8175T>G	p.Ile2725Met	missense_variant	56/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 linkuse as main transcript	c.8238T>G	p.Ile2746Met	missense_variant	57/58	1	NM_001042492.3	ENSP00000351015	P1	P21359-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000795

AC:

AN:

251440

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135888

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000458

AC:

AN:

1461854

Hom.:

Cov.:

AF XY:

0.0000468

AC XY:

AN XY:

727224

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:

0.0000585

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

Cov.:

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.00

AC:

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:6Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Neurofibromatosis, type 1

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Johns Hopkins Genomics, Johns Hopkins University	Apr 01, 2021	NF1 c.8238T>G (rs779789452) is rare (<0.1%) in a large population dataset (gnomAD: 2/251440 total alleles; 0.0008%; no homozygotes) and has not been reported in the literature, to our knowledge. This variant has been reported in ClinVar (Variation ID: 231655). Three bioinformatic tools queried predict that this substitution would be tolerated, however the isoleucine residue at this position is evolutionarily conserved across most species assessed. We consider the clinical significance of NF1 c.8238T>G to be uncertain at this time. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Mar 15, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 08, 2024	This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 2725 of the NF1 protein (p.Ile2725Met). This variant is present in population databases (rs779789452, gnomAD 0.002%). 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: 231655). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae 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. -

NF1-related disorder

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jun 03, 2024

The NF1 c.8238T>G variant is predicted to result in the amino acid substitution p.Ile2746Met. To our knowledge, this variant has not been reported in the literature. This variant is reported in 2 of 251,000 alleles in gnomAD. It has conflicting interpretations of likely benign and uncertain significance in ClinVar (https://preview.ncbi.nlm.nih.gov/clinvar/variation/231655/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Neurofibromatosis, type 1;C0349639:Juvenile myelomonocytic leukemia;C0553586:Café-au-lait macules with pulmonary stenosis;C1834235:Neurofibromatosis, familial spinal;C2931482:Neurofibromatosis-Noonan syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 18, 2021

- -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 13, 2015

The p.I2746M variant (also known as c.8238T>G), located in coding exon 57 of the NF1 gene, results from a T to G substitution at nucleotide position 8238. The isoleucine at codon 2746 is replaced by methionine, 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 0.003% (greater than 110000 alleles tested) in our clinical cohort. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of p.I2746M remains unclear. -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 04, 2023

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.062

BayesDel_addAF

Benign

-0.21

BayesDel_noAF

Benign

-0.53

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.45

T;.;T

Eigen

Benign

0.17

Eigen_PC

Uncertain

0.24

FATHMM_MKL

Uncertain

0.89

LIST_S2

Uncertain

0.91

D;D;D

M_CAP

Uncertain

0.086

MetaRNN

Benign

0.17

T;T;T

MetaSVM

Benign

-0.99

MutationAssessor

Benign

1.2

L;.;.

MutationTaster

Benign

0.93

D;D;D;D

PrimateAI

Uncertain

0.73

PROVEAN

Benign

-0.89

N;N;N

REVEL

Benign

0.040

Sift

Benign

0.20

T;T;T

Sift4G

Benign

0.070

T;T;T

Polyphen

0.68

P;P;.

Vest4

0.28

MutPred

0.24

Gain of phosphorylation at Y2742 (P = 0.0775);.;.;

MVP

0.46

MPC

0.91

ClinPred

0.43

GERP RS

4.0

Varity_R

0.11

gMVP

0.14

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

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