17-31265308-G-A

Position:

• chr17-31265308-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_001042492.3(NF1):​c.4804G>A​(p.Gly1602Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,786 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 (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:6
• Conservation: PhyloP100: 9.32

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 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a region_of_interest Lipid binding (size 257) in uniprot entity NF1_HUMAN there are 37 pathogenic changes around while only 10 benign (79%) in NM_001042492.3
• PM2: Very rare variant in population databases, with high coverage
• 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, 0.924

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NF1	NM_001042492.3	c.4804G>A	p.Gly1602Arg	missense_variant	36/58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.4741G>A	p.Gly1581Arg	missense_variant	35/57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.4804G>A	p.Gly1602Arg	missense_variant	36/58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460786 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726788

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 11, 2024	This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 1581 of the NF1 protein (p.Gly1581Arg). 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: 237570). 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%. 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Mar 15, 2022	- -

NF1-related disorder Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 01, 2024

The NF1 c.4804G>A variant is predicted to result in the amino acid substitution p.Gly1602Arg. To our knowledge, this variant has not been reported in the literature or in gnomAD, indicating this variant is rare. This variant is interpreted as uncertain in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/237570/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Mar 28, 2023

Not observed 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 -

Juvenile myelomonocytic leukemia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Jul 19, 2023

- -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 18, 2023

The p.G1581R variant (also known as c.4741G>A), located in coding exon 35 of the NF1 gene, results from a G to A substitution at nucleotide position 4741. The glycine at codon 1581 is replaced by arginine, an amino acid with dissimilar properties. 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 this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.64
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.90	D;.;T
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D;D;D
M_CAP	Pathogenic	0.63	D
MetaRNN	Pathogenic	0.92	D;D;D
MetaSVM	Uncertain	-0.077	T
MutationAssessor	Uncertain	2.1	M;.;.
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-5.8	D;D;D
REVEL	Uncertain	0.60
Sift	Uncertain	0.0040	D;D;D
Sift4G	Pathogenic	0.0010	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.82
MutPred		0.75		Gain of MoRF binding (P = 0.0211);.;.;
MVP		0.91
MPC		1.9
ClinPred		0.97	D
GERP RS		6.2
Varity_R		0.87
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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

Other links and lift over

dbSNP: rs878853898; hg19: chr17-29592326; COSMIC: COSV62222093; COSMIC: COSV62222093;