17-31357046-G-C

Variant names:

• chr17-31357046-G-C
• rs786203848
• NM_001042492.3:c.7825G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001042492.3(NF1):​c.7825G>C​(p.Val2609Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,628 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V2609I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 8.97
• Publications: 2 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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.7825G>C	p.Val2609Leu	missense_variant	Exon 53 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.7762G>C	p.Val2588Leu	missense_variant	Exon 52 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.7825G>C	p.Val2609Leu	missense_variant	Exon 53 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461628 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727114

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39684

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53260

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111932

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Uncertain:2

Mar 15, 2022

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

May 05, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 2588 of the NF1 protein (p.Val2588Leu). 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: 527447). 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

Mar 23, 2018

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is denoted NF1 c.7762G>C at the cDNA level, p.Val2588Leu (V2588L) at the protein level, and results in the change of a Valine to a Leucine (GTA>CTA). This variant has not, to our knowledge, been published in the literature as pathogenic or benign. NF1 Val2588Leu was not observed in large population cohorts (Lek 2016). This variant is located in the C-terminal domain (Luo 2014). In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function. Based on currently available evidence, it is unclear whether NF1 Val2588Leu is a pathogenic or benign variant. We consider it to be a variant of uncertain significance.

Juvenile myelomonocytic leukemia Uncertain:1

Dec 02, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.63
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.030
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.62	D;.;T
Eigen	Pathogenic	0.82
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D;D;D
M_CAP	Uncertain	0.28	D
MetaRNN	Uncertain	0.54	D;D;D
MetaSVM	Benign	-0.38	T
MutationAssessor	Benign	1.8	L;.;.
PhyloP100		9.0
PrimateAI	Pathogenic	0.84	D
PROVEAN	Benign	-2.2	N;N;N
REVEL	Benign	0.23
Sift	Uncertain	0.011	D;D;D
Sift4G	Uncertain	0.011	D;D;D
Vest4		0.68
ClinPred		0.93	D
GERP RS		5.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.44
gMVP		0.56
Mutation Taster		=5/95	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: rs786203848; hg19: chr17-29684064;