chr17-31229157-G-C

Variant names:

• chr17-31229157-G-C
• rs1060500368
• NM_001042492.3:c.2542G>C

Variant summary

Our verdict is Pathogenic. The variant received 26 ACMG points: 26P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_001042492.3(NF1):​c.2542G>C​(p.Gly848Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G848E) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 9.56
• Publications: 22 publications found

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 Gene-Disease associations (from GenCC):

• neurofibromatosis type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, PanelApp Australia, G2P, Genomics England PanelApp
• neurofibromatosis-Noonan syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp, PanelApp Australia
• Moyamoya disease

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• hereditary pheochromocytoma-paraganglioma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial ovarian cancer

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 26 ACMG points.

• PS1: Transcript NM_001042492.3 (NF1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 33 uncertain 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 chr17-31229158-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 68324.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981
• PP5: Variant 17-31229157-G-C is Pathogenic according to our data. Variant chr17-31229157-G-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 404588.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.2542G>C	p.Gly848Arg	missense_variant	Exon 21 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.2542G>C	p.Gly848Arg	missense_variant	Exon 21 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.2542G>C	p.Gly848Arg	missense_variant	Exon 21 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:3

Mar 15, 2022

Genome-Nilou Lab

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 05, 2019

UAB Medical Genomics Laboratory, UAB Medicine

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jul 24, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 848 of the NF1 protein (p.Gly848Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with neurofibromatosis type 1 and neurofibromatosis (PMID: 17712740, 27482814, 29290338; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 404588). 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 with a positive predictive value of 95%. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on NF1 function (PMID: 26908603, 27482814). This variant disrupts the p.Gly848 amino acid residue in NF1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 12552569, 23812910, 25211147, 29290338). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Dec 06, 2024

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); Segregates with disease in individuals with spinal neurofibromatosis from a single family in the published literature (PMID: 17712740); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 24803665, 26908603, 27482814, 12552569, 37891793, 32408052, 27171602, 34945792, 38318325, 32642668, 29246098, 27269372, 25486365, 2121369, 23812910, 25211147, 34694046, 38837168, 35433111, 30963251, 38816530, 36689660, 33919865, 31776437, 29290338, 17712740) -

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Pathogenic:1

Oct 21, 2020

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.G848R pathogenic mutation (also known as c.2542G>C), located in coding exon 21 of the NF1 gene, results from a G to C substitution at nucleotide position 2542. The glycine at codon 848 is replaced by arginine, an amino acid with dissimilar properties. This mutation occurred de novo in one individual with a clinical or suspected diagnosis of neurofibromatosis type 1 (NF1) and co-segregated with NF1 in five unrelated families (Koczkowska M et al. Am. J. Hum. Genet., 2018 01;102:69-87). The alteration was also reported in a family with spinal neurofibromatosis (Pascual-Castroviejo I et al. Neuropediatrics, 2007 Apr;38:105-8). While mouse models harboring this mutation did not recapitulate the phenotype in humans, these mice had reduced neurofibromin expression (Li K et al. Dis Model Mech, 2016 07;9:759-67; Toonen JA et al. Hum. Mol. Genet., 2016 05;25:1703-13). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.97	D;.;D
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.76	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Benign	-0.76	T
MutationAssessor	Benign	1.8	L;L;.
PhyloP100		9.6
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-6.3	D;D;D
REVEL	Pathogenic	0.74
Sift	Uncertain	0.0010	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		1.0
MutPred		0.92		Gain of MoRF binding (P = 0.0316);Gain of MoRF binding (P = 0.0316);.;
MVP		0.90
MPC		1.9
ClinPred		1.0	D
GERP RS		5.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.90
gMVP		0.93
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1060500368; hg19: chr17-29556175;