17-31330473-G-C

Variant names:

• chr17-31330473-G-C
• rs786202591
• NM_001042492.3:c.5787G>C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PP3

The NM_001042492.3(NF1):​c.5787G>C​(p.Glu1929Asp) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1929Q) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:4
• Conservation: PhyloP100: 3.80
• Publications: 0 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: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 24 uncertain in NM_001042492.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.828

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.5787G>C	p.Glu1929Asp	missense_variant	Exon 39 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.5724G>C	p.Glu1908Asp	missense_variant	Exon 38 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.5787G>C	p.Glu1929Asp	missense_variant	Exon 39 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:4

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1 Uncertain:2

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jun 22, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. 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. ClinVar contains an entry for this variant (Variation ID: 185958). This variant has not been reported in the literature in individuals affected with NF1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 1908 of the NF1 protein (p.Glu1908Asp).

Feb 05, 2025

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is classified as Likely pathogenic. Evidence in support of pathogenic classification: Variant is absent from gnomAD (v2, v3 and v4); This variant has limited previous evidence of pathogenicity in unrelated individuals. This variant has four VUS reports, and an alternate nucleotide change resulting in the same amino acid substitution has four VUS reports and one de novo likely pathogenic report (ClinVar); Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change; This variant has been shown to be de novo in the proband (parental status confirmed) (by trio analysis). Additional information: Variant is predicted to result in a missense amino acid change from glutamic acid to aspartic acid; This variant is heterozygous; This gene is associated with autosomal dominant disease; No published segregation evidence has been identified for this variant; No published functional evidence has been identified for this variant; Other missense variants comparable to the one identified in this case have inconclusive previous evidence for pathogenicity. Three alternate missense variants at the same amino acid position have VUS reports (ClinVar); Variant is not located in an established domain, motif, hotspot or informative constraint region; Loss of function is a known mechanism of disease in this gene and is associated juvenile myelomonocytic leukemia (MIM#607785), familial spinal neurofibromatosis (MIM#162210), neurofibromatosis, type 1 (MIM#162200), neurofibromatosis-Noonan syndrome (MIM#601321) and Watson syndrome (MIM#193520); Variants in this gene are known to have variable expressivity. Disease manifestation can be extremely variable, even within a family (PMID: 20301288).

not provided Uncertain:1

Mar 30, 2023

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge

Hereditary cancer-predisposing syndrome Uncertain:1

Aug 21, 2014

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.E1929D variant (also known as c.5787G>C), located in coding exon 39 of the NF1 gene, results from a G to C substitution at nucleotide position 5787. The glutamic acid at codon 1929 is replaced by aspartic acid, 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 0.01% (greater than 11000 alleles tested) in our clinical cohort. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be possibly damaging and deleterious by PolyPhen and SIFT in silico analyses, respectively. Since supporting evidence is limited at this time, the clinical significance of p.E1929D remains unclear.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D;.;D;.
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.56
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.93	D;D;D;D
M_CAP	Pathogenic	0.82	D
MetaRNN	Pathogenic	0.83	D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	2.9	M;.;.;.
PhyloP100		3.8
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-2.6	D;D;N;.
REVEL	Pathogenic	0.83
Sift	Pathogenic	0.0	D;D;D;.
Sift4G	Pathogenic	0.0	D;D;D;.
Vest4		0.82
ClinPred		0.99	D
GERP RS		4.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.72
gMVP		0.85
Mutation Taster		=24/76	disease causing

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

Other links and lift over

dbSNP: rs786202591; hg19: chr17-29657491;