NM_001042492.3:c.3468C>A

Variant names:

• chr17-31232853-C-A
• rs147955381
• NM_001042492.3:c.3468C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3 PP5_Moderate

The NM_001042492.3(NF1):​c.3468C>A​(p.Asn1156Lys) variant causes a missense change involving the alteration of a non-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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N1156S) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: NF1 NM_001042492.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: -1.66
• Publications: 6 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 41 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 chr17-31232852-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 68332.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.767
• PP5: Variant 17-31232853-C-A is Pathogenic according to our data. Variant chr17-31232853-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 527521.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NF1	NM_001042492.3	c.3468C>A	p.Asn1156Lys	missense_variant	Exon 26 of 58	ENST00000358273.9	NP_001035957.1
NF1	NM_000267.4	c.3468C>A	p.Asn1156Lys	missense_variant	Exon 26 of 57		NP_000258.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NF1	ENST00000358273.9	c.3468C>A	p.Asn1156Lys	missense_variant	Exon 26 of 58	1	NM_001042492.3	ENSP00000351015.4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neurofibromatosis, type 1 Pathogenic:1

Apr 26, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant is observed to be de novo in an individual affected with NF1-related disease (Invitae). This variant is not present in population databases (ExAC no frequency). This sequence change replaces asparagine with lysine at codon 1156 of the NF1 protein (p.Asn1156Lys). The asparagine residue is moderately conserved and there is a moderate physicochemical difference between asparagine and lysine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Benign	-0.081	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.97	D;.;D
Eigen	Benign	-0.43
Eigen_PC	Benign	-0.67
FATHMM_MKL	Benign	0.33	N
LIST_S2	Pathogenic	0.98	D;D;D
M_CAP	Pathogenic	0.89	D
MetaRNN	Pathogenic	0.77	D;D;D
MetaSVM	Benign	-0.64	T
MutationAssessor	Pathogenic	3.3	M;M;.
PhyloP100		-1.7
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-4.8	D;D;D
REVEL	Uncertain	0.47
Sift	Pathogenic	0.0	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;D;.
Vest4		0.98
MutPred		0.75		Loss of stability (P = 0.0045);Loss of stability (P = 0.0045);.;
MVP		0.80
MPC		1.8
ClinPred		1.0	D
GERP RS		-5.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.91
gMVP		0.98
Mutation Taster		=23/77	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.17		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: rs147955381; hg19: chr17-29559871;