rs199474773

Variant names:

• chr17-31200546-A-G
• rs199474773
• NM_001042492.3:c.1013A>G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2 PP2 PP3 PP5_Very_Strong

The NM_001042492.3(NF1):​c.1013A>G​(p.Asp338Gly) 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. Variant has been reported in ClinVar as Likely 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:3 O:1
• Conservation: PhyloP100: 8.58

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 12 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the NF1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 399 curated pathogenic missense variants (we use a threshold of 10). The gene has 143 curated benign missense variants. Gene score misZ: 6.5427 (above the threshold of 3.09). Trascript score misZ: 8.4054 (above the threshold of 3.09). GenCC associations: The gene is linked to neurofibromatosis, familial spinal, hereditary pheochromocytoma-paraganglioma, neurofibromatosis type 1, Watson syndrome, neurofibromatosis-Noonan syndrome, Moyamoya disease, familial ovarian cancer.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-31200546-A-G is Pathogenic according to our data. Variant chr17-31200546-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 68297.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.1013A>G	p.Asp338Gly	missense_variant	Exon 9 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.3	c.1013A>G	p.Asp338Gly	missense_variant	Exon 9 of 57		NP_000258.1
NF1	NM_001128147.3	c.1013A>G	p.Asp338Gly	missense_variant	Exon 9 of 15		NP_001121619.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.1013A>G	p.Asp338Gly	missense_variant	Exon 9 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:2

May 29, 2024

Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 01, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 338 of the NF1 protein (p.Asp338Gly). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of neurofibromatosis type I (PMID: 9298829, 30014477, 31730495, 33911094; Invitae). ClinVar contains an entry for this variant (Variation ID: 68297). 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%. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1 Other:1

Nov 04, 2022

GeneDx

Significance: Likely pathogenic

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; In silico analysis supports a deleterious effect on splicing; This variant is associated with the following publications: (PMID: 24803665, 9298829, 31730495, 33911094, Kamis2021[article], 30014477) -

-

UniProtKB/Swiss-Prot

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.84
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.25
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.74	.;D;.;.;T
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D
M_CAP	Pathogenic	0.88	D
MetaRNN	Pathogenic	0.88	D;D;D;D;D
MetaSVM	Uncertain	-0.084	T
MutationAssessor	Uncertain	2.3	M;M;M;M;.
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.4	.;D;D;D;N
REVEL	Uncertain	0.64
Sift	Benign	0.065	.;T;T;D;T
Sift4G	Uncertain	0.0080	.;D;D;D;T
Polyphen		0.99	D;B;D;.;.
Vest4		0.97, 0.95, 0.96
MutPred		0.67		Loss of stability (P = 0.0311);Loss of stability (P = 0.0311);Loss of stability (P = 0.0311);Loss of stability (P = 0.0311);.;
MVP		0.95
MPC		2.0
ClinPred		0.98	D
GERP RS		5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.0
Varity_R		0.41
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.55		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.46		Position offset: -1
DS_DL_spliceai		0.55		Position offset: 49

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

Publications

LitVar

Other links and lift over

dbSNP: rs199474773; hg19: chr17-29527564;