rs1555614858

chr17-31232152-G-Achr17-31232152-G-C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5_Moderate

The NM_001042492.3(NF1):c.3277G>A(p.Val1093Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V1093A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 29)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 9.49

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 14 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 chr17-31232153-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 1397020.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant where missense usually causes diseases, NF1
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-31232152-G-A is Pathogenic according to our data. Variant chr17-31232152-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 457638.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr17-31232152-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NF1	NM_001042492.3	c.3277G>A	p.Val1093Met	missense_variant	25/58	ENST00000358273.9
NF1	NM_000267.3	c.3277G>A	p.Val1093Met	missense_variant	25/57

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NF1	ENST00000358273.9	c.3277G>A	p.Val1093Met	missense_variant	25/58	1	NM_001042492.3	P1

Frequencies

GnomAD3 genomes Cov.: 29

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 29

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:2

Likely pathogenic, no assertion criteria provided	research	Rajaie Cardiovascular, Medical and Research Center, Iran University of Medical Sciences	-	The NF1 gene encodes Neurofibromin, a cytoplasmic protein that is predominantly expressed in neurons, Schwann cells, oligodendrocytes, and leukocytes. Mutations in NF1 result in Neurofibromatosis type 1 with an autosomal dominant inheritance (OMIM: 162200). -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Oct 22, 2023	This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 1093 of the NF1 protein (p.Val1093Met). RNA analysis indicates that this missense change induces altered splicing and may result in an absent or disrupted protein product. This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with neurofibromatosis type 1 (PMID: 10862084, 18546366, 23913538). ClinVar contains an entry for this variant (Variation ID: 457638). 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. Studies have shown that this missense change results in a new splice site within exon 25 and deletes 40 nucleotides from the exon and introduces a premature termination codon (PMID: 10862084, 23913538; Invitae). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.019	T
BayesDel_noAF	Benign	-0.26
Cadd	Pathogenic	35
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.57	D;.;T
Eigen	Uncertain	0.65
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D;D;D
M_CAP	Pathogenic	0.88	D
MetaRNN	Uncertain	0.47	T;T;T
MetaSVM	Benign	-1.2	T
MutationAssessor	Uncertain	2.1	M;M;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-0.85	N;N;N
REVEL	Benign	0.24
Sift	Benign	0.064	T;T;T
Sift4G	Benign	0.062	T;T;T
Polyphen		0.98	D;D;.
Vest4		0.63
MutPred		0.28		Loss of catalytic residue at V1093 (P = 0.0291);Loss of catalytic residue at V1093 (P = 0.0291);.;
MVP		0.43
MPC		1.7
ClinPred		0.95	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.24
gMVP		0.33

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.83		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.83		Position offset: -3
DS_DL_spliceai		0.40		Position offset: 37

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555614858; hg19: chr17-29559170;