17-31232779-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4BP6BS2_Supporting

The NM_001042492.3(NF1):​c.3394C>T​(p.Arg1132Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000093 in 1,613,634 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1132H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

NF1
NM_001042492.3 missense

Scores

6
8
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:2

Conservation

PhyloP100: 1.59

Publications

5 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.3905633).
BP6
Variant 17-31232779-C-T is Benign according to our data. Variant chr17-31232779-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 141407.
BS2
High AC in GnomAdExome4 at 14 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001042492.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NF1
NM_001042492.3
MANE Select
c.3394C>Tp.Arg1132Cys
missense
Exon 26 of 58NP_001035957.1
NF1
NM_000267.4
c.3394C>Tp.Arg1132Cys
missense
Exon 26 of 57NP_000258.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
NF1
ENST00000358273.9
TSL:1 MANE Select
c.3394C>Tp.Arg1132Cys
missense
Exon 26 of 58ENSP00000351015.4
NF1
ENST00000356175.7
TSL:1
c.3394C>Tp.Arg1132Cys
missense
Exon 26 of 57ENSP00000348498.3
NF1
ENST00000579081.6
TSL:1
n.3394C>T
non_coding_transcript_exon
Exon 26 of 58ENSP00000462408.2

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151770
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251412
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000958
AC:
14
AN:
1461864
Hom.:
0
Cov.:
32
AF XY:
0.00000688
AC XY:
5
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0000383
AC:
1
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000989
AC:
11
AN:
1111990
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000659
AC:
1
AN:
151770
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
74090
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41322
American (AMR)
AF:
0.00
AC:
0
AN:
15234
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4762
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10546
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67936
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000508
Hom.:
0
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Neurofibromatosis, type 1 Uncertain:2Benign:1
Aug 17, 2022
Medical Genetics, University of Parma
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Mar 15, 2022
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Astrocytoma IDH-mutant Uncertain:1
May 31, 2021
Laboratory of Medical Genetics Unit, Bambino Gesù Children's Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

not provided Uncertain:1
Aug 01, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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; This variant is associated with the following publications: (PMID: 25486365, 2121369, 22807134, Martorana2022[CaseReport])

Hereditary cancer-predisposing syndrome Uncertain:1
Oct 13, 2015
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R1132C variant (also known as c.3394C>T), located in coding exon 26 of the NF1 gene, results from a C to T substitution at nucleotide position 3394. The arginine at codon 1132 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant was not reported in population based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. To date, this alteration has been detected with an allele frequency of approximately 0.01% (greater than 55000 alleles tested) in our clinical cohort.This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive.Since supporting evidence is limited at this time, the clinical significance of this variant remains unclear.

Hereditary cancer-predisposing syndrome;CN230736:Cardiovascular phenotype Benign:1
Mar 26, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.70
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Uncertain
-0.030
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.86
D
Eigen
Uncertain
0.23
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Pathogenic
0.68
D
MetaRNN
Benign
0.39
T
MetaSVM
Benign
-1.2
T
MutationAssessor
Benign
1.2
L
PhyloP100
1.6
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-3.7
D
REVEL
Benign
0.20
Sift
Uncertain
0.0030
D
Sift4G
Uncertain
0.0070
D
Polyphen
0.089
B
Vest4
0.85
MutPred
0.41
Gain of sheet (P = 0.0221)
MVP
0.78
MPC
2.0
ClinPred
0.94
D
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.8
Varity_R
0.40
gMVP
0.27
Mutation Taster
=41/59
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

Publications

Other links and lift over

dbSNP: rs587781725; hg19: chr17-29559797; COSMIC: COSV99049878; API