17-31235651-G-A

Position:

chr17-31235651-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PM5PP2PP3

The NM_001042492.3(NF1):c.3749G>A(p.Arg1250Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,746 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1250P) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6

Conservation

PhyloP100: 9.41

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_pathogenic. Variant got 8 ACMG points.

PM1

In a domain Ras-GAP (size 216) in uniprot entity NF1_HUMAN there are 42 pathogenic changes around while only 3 benign (93%) in NM_001042492.3

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.

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.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.788

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3 linkuse as main transcript	c.3749G>A	p.Arg1250Gln	missense_variant	28/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3 linkuse as main transcript	c.3749G>A	p.Arg1250Gln	missense_variant	28/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9 linkuse as main transcript	c.3749G>A	p.Arg1250Gln	missense_variant	28/58	1	NM_001042492.3	ENSP00000351015	P1	P21359-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151928

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:

1461818

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

727214

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:

0.00000658

AC:

AN:

151928

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74192

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:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Neurofibromatosis, type 1

Uncertain:2

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	Sep 10, 2023	This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 1250 of the NF1 protein (p.Arg1250Gln). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. 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: 233335). 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 expected to disrupt NF1 protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

May 11, 2021

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as a germline pathogenic or benign variant in individual(s) with neurofibromatosis type 1 to our knowledge; This variant is associated with the following publications: (PMID: 24476948, 33935721, 25486365, 22807134, 32697994) -

Juvenile myelomonocytic leukemia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Feb 12, 2024

- -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 09, 2020

The c.3749G>A (p.R1250Q) alteration is located in exon 28 (coding exon 28) of the NF1 gene. This alteration results from a G to A substitution at nucleotide position 3749, causing the arginine (R) at amino acid position 1250 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 10, 2015

The p.R1250Q variant (also known as c.3749G>A), located in coding exon 28 of the NF1 gene, results from a G to A substitution at nucleotide position 3749. The arginine at codon 1250 is replaced by glutamine, an amino acid with highly similar properties. This alteration wasdetected in acohortof 30non-aneuploidfetuses and neonateswith diverse structural abnormalities first identified by prenatal ultrasound (CarssKJ et al.Hum Mol Genet. 2014 Jun 15;23(12):3269-77).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 0.002% (greater than 55000alleles tested) in our clinical cohort.This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis.Since supporting evidence is limited at this time, the clinical significance of p.R1250Qremains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.45

BayesDel_addAF

Pathogenic

0.37

BayesDel_noAF

Pathogenic

0.29

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.62

D;.;T

Eigen

Uncertain

0.58

Eigen_PC

Pathogenic

0.68

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.97

D;D;D

M_CAP

Pathogenic

0.72

MetaRNN

Pathogenic

0.79

D;D;D

MetaSVM

Uncertain

0.25

MutationAssessor

Benign

0.45

N;N;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.84

PROVEAN

Benign

-1.7

N;N;N

REVEL

Pathogenic

0.74

Sift

Uncertain

0.0090

D;D;D

Sift4G

Uncertain

0.0050

D;D;D

Polyphen

0.99

D;D;.

Vest4

0.88

MutPred

0.56

Gain of catalytic residue at R1250 (P = 0.1486);Gain of catalytic residue at R1250 (P = 0.1486);.;

MVP

0.97

MPC

1.4

ClinPred

0.84

GERP RS

5.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.60

gMVP

0.55

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.25

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.25

Position offset: 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